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IBM® Workplace Forms™ Server - API
COM API User's Manual
Version 2.6
S229-1528-00

Note
Before using this information and the product it supports, read the information in “Notices,” on page 157.
First Edition (September 2006)
This edition applies to version 2.6 of IBM Workplace Forms Server - API (product number L-DSED-6JLR37) and to
all subsequent releases and modifications until otherwise indicated in new editions.
© Copyright International Business Machines Corporation 2003, 2006. All rights reserved.
US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract
with IBM Corp.
Contents
Introduction . . . . . . . . . . . . .1
About This Manual . . . . . . . . . . . .1
Who Should Read This Manual . . . . . . .1
Document Conventions . . . . . . . . . .1
About the API . . . . . . . . . . . .3
Where the API Fits in Your System . . . . . . .3
Differences Between the C, Java, and COM Editions
of the API . . . . . . . . . . . . . . .3
The API Data Types . . . . . . . . . . . .4
IFormNodeP Objects . . . . . . . . . . .4
About the API Constants . . . . . . . . . .4
Overview of the Form Structure . . . .5
The Node Structure . . . . . . . . . . . .5
The Node Hierarchy . . . . . . . . . . . .5
References . . . . . . . . . . . . . . .6
Dereferencing . . . . . . . . . . . . .7
Namespace in References . . . . . . . . .8
Advanced Information about the Node Structure . .8
A Sample Hierarchy . . . . . . . . . . .9
The Sample Tree Structure . . . . . . . . .9
Node Properties . . . . . . . . . . . .10
Introduction to the Form Library . . . .13
Getting Started with the Form Library 15
Setting Up Your Application . . . . . . . . .15
Initializing the Form Library . . . . . . . . .16
Loading a Form . . . . . . . . . . . . .17
Retrieving A Value from a Form . . . . . . .17
Setting a Value in a Form . . . . . . . . . .18
Writing a Form to Disk . . . . . . . . . .19
Closing a Form . . . . . . . . . . . . .20
Compiling Your Application . . . . . . . . .20
Testing your Application . . . . . . . . . .20
Distributing Applications That Use the Form Library 21
Summary . . . . . . . . . . . . . . .21
Form Library Quick Reference Guide 23
Form Library Functions . . . . . . . . . .23
About the Function Descriptions . . . . . . .26
Using Signatures with the Form Library . . . . .26
About Errors . . . . . . . . . . . . . .26
About Output Parameters . . . . . . . . .27
The Certificate Functions . . . . . . .29
GetBlob . . . . . . . . . . . . . . . .29
GetDataByPath . . . . . . . . . . . . .30
GetIssuer . . . . . . . . . . . . . . .33
The FormNodeP Functions . . . . . .35
FormNodeP Constants . . . . . . . . . . .35
addNamespace . . . . . . . . . . . . .35
CheckValidFormats . . . . . . . . . . . .37
createCell . . . . . . . . . . . . . . .37
DeleteSignature . . . . . . . . . . . . .38
DereferenceEx . . . . . . . . . . . . .40
Destroy . . . . . . . . . . . . . . . .44
Duplicate . . . . . . . . . . . . . . .45
EncloseFile . . . . . . . . . . . . . .46
EncloseInstance . . . . . . . . . . . . .47
ExtractFile . . . . . . . . . . . . . . .48
ExtractInstance . . . . . . . . . . . . .49
ExtractXFormsInstance . . . . . . . . . .51
GetAttribute . . . . . . . . . . . . . .52
GetCertificateList . . . . . . . . . . . .54
GetChildren . . . . . . . . . . . . . .55
GetFormVersion . . . . . . . . . . . . .56
GetIdentifier . . . . . . . . . . . . . .57
GetLiteralByRefEx . . . . . . . . . . . .58
GetLiteralEx . . . . . . . . . . . . . .61
GetLocalName . . . . . . . . . . . . .62
GetNamespaceURI . . . . . . . . . . . .63
GetNamespaceURIFromPrefix . . . . . . . .64
GetNext . . . . . . . . . . . . . . .66
GetNodeType . . . . . . . . . . . . . .67
GetParent . . . . . . . . . . . . . . .68
GetPrefix . . . . . . . . . . . . . . .69
GetPrefixFromNamespaceURI . . . . . . . .71
GetPrevious . . . . . . . . . . . . . .72
GetReferenceEx . . . . . . . . . . . . .73
GetSecurityEngineName . . . . . . . . . .77
GetSigLockCount . . . . . . . . . . . .78
GetSignature . . . . . . . . . . . . . .78
GetSignatureVerificationStatus . . . . . . . .80
GetType . . . . . . . . . . . . . . .81
IsSigned . . . . . . . . . . . . . . .82
IsValidFormat . . . . . . . . . . . . .83
IsXFDL . . . . . . . . . . . . . . . .84
RemoveAttribute . . . . . . . . . . . .85
RemoveEnclosure . . . . . . . . . . . .86
ReplaceXFormsInstance . . . . . . . . . .87
SetActiveForComputationalSystem . . . . . .88
SetAttribute . . . . . . . . . . . . . .89
SetFormula . . . . . . . . . . . . . .91
SetLiteralByRefEx . . . . . . . . . . . .92
SetLiteralEx . . . . . . . . . . . . . .95
SignForm . . . . . . . . . . . . . . .96
UpdateXFormsInstance . . . . . . . . . .97
ValidateHMACWithSecret . . . . . . . . .99
ValidateHMACWithHashedSecret . . . . . . 102
VerifyAllSignatures . . . . . . . . . . . 106
VerifySignature . . . . . . . . . . . . . 107
WriteForm . . . . . . . . . . . . . . 109
WriteFormToASPResponse . . . . . . . . .110
XMLModelUpdate . . . . . . . . . . . . 111
The Hash Functions . . . . . . . .113
© Copyright IBM Corp. 2003, 2006 iii
Hash . . . . . . . . . . . . . . . .113
The Initialization Functions . . . . .117
IFSInitialize . . . . . . . . . . . . . .117
IFSInitializeWithLocale . . . . . . . . . .119
The LocalizationManager Functions 123
GetCurrentThreadLocale . . . . . . . . . . 123
GetDefaultLocale . . . . . . . . . . . . 125
SetCurrentThreadLocale . . . . . . . . . . 128
SetDefaultLocale . . . . . . . . . . . . 130
The SecurityManager Functions . . . 135
LookupHashAlgorithm . . . . . . . . . . 135
The Signature Functions . . . . . . 139
GetDataByPath . . . . . . . . . . . . . 139
GetSigningCert . . . . . . . . . . . . . 144
The XFDL Functions . . . . . . . . 147
Create . . . . . . . . . . . . . . . . 147
GetEngineCertificateList . . . . . . . . . . 149
IsDigitalSignaturesAvailable . . . . . . . . 151
ReadForm . . . . . . . . . . . . . . 152
ReadFormFromASPRequest . . . . . . . . 154
Appendix. Notices . . . . . . . . . 157
Trademarks . . . . . . . . . . . . . . 158
Index . . . . . . . . . . . . . . . 159
iv
Introduction
Welcome to the COM Edition of the user’s manual for the IBM® Workplace Forms™
Server — API. The API extends the capabilities of Workplace Forms by enabling
you to:
v Manipulate XFDL forms from new or existing applications.
v Create custom-built functions that may be integrated into XFDL forms.
This section discusses the organization and format of this manual. To learn more
about the API, refer to “About the API” on page 3.
About This Manual
This manual has been organized as both an instruction manual and a quick
reference. It describes the functions available in the API and provides examples of
their use.
This manual contains the following major sections:
Section Page
Introduction — introduces you to the
features of the API.
“Introduction”
Overview of the Form Structure — explains
how XFDL forms are stored in memory.
“Overview of the Form Structure” on page 5
Getting Started with the Form Library —
provides a detailed tutorial demonstrating
how to create a simple application that
interacts with an XFDL form.
“Introduction to the Form Library” on page
13
Form Library Quick Reference — a
reference to the functions contained in the
Form Library. Each method description
includes sample code.
“Form Library Quick Reference Guide” on
page 23
Who Should Read This Manual
The API is designed to be easy to use for any moderately experienced programmer.
However, the skill level required to develop particular functions may be quite
high. This document is intended for developers who have a working knowledge
of:
v COM compliant programming and syntax.
v Extensible Forms Description Language (XFDL) and syntax. Refer to the
Extensible Forms Description Language Specification for more information.
Document Conventions
The following conventions appear throughout this manual:
v Sample code is presented in a monospaced font, and is indented to make the
code stand out:
© Copyright IBM Corp. 2003, 2006 1
Sub SaveForm(Form, ThePath)
’ Write the form to a file on disk
Form.WriteForm ThePath, Nothing, 0
End Sub
v Text in bold italics represents information that you need to supply:
<label sid="firstName">
<value>your first name here</value>
<label>
v The hash symbol (#) represents a number.
v Angle brackets enclose placeholders. For example, <API Program Folder>
represents the actual folder in which you installed the API.
v Braces indicate optional items. The following example indicates that the item tag
(including the period after it) is optional:
{itemtag.} option
v ″xx″ or ″xxx″ appears in place of the two or three digit version number of the
API. In particular, these placeholders appear when referring to file names,
folders, and directories that contain the API’s version number.
v Brackets are used to indicate a sequence of choices, and the pipe symbol ( | ) is
used to indicate ″or″. The following example indicates that you can use a
number or a name:
(number|name)
2
About the API
The Workplace Forms Server — Application Programmer Interface (API) consists of
a collection of programming tools to help you develop applications that can
interact with XFDL forms. These tools are available for both C and Java
programming environments. The API enables you to access and manipulate forms
as structured data types.
The API is divided into two libraries: the Form Library and the Function Call
Interface (FCI) Library. The Form Library allows you to create applications that:
v Read and write forms.
v Retrieve information from form elements.
v Add cells to certain form items.
v Insert information into form elements.
For more information about the Form Library refer to the “Form Library Quick
Reference Guide” on page 23.
Where the API Fits in Your System
IBM provides a powerful suite of forms software for creating, using and
transmitting forms over the Internet. The main components of this suite are:
Workplace Forms Viewer — Use the Viewer to view XFDL forms just as you
would use a web browser to view HTML pages. You can also use the Viewer to fill
out forms and submit them for review.
Workplace Forms Designer — The Designer provides an easy to use WYSIWYG
design environment for creating XFDL forms. Use the Designer to create forms
quickly and easily.
Workplace Forms API — The API is made up of a collection of Form functions.
Use the Form Library to develop applications that manipulate XFDL forms.
Differences Between the C, Java, and COM Editions of the API
The various editions of the API differ in the following ways:
v The Java and COM editions offer an object-oriented interface.
v The COM edition does not support the FCI Library.
v The COM edition does not include the following Form Library functions:
– GetInfoEx
– GetAttributeList
v
The COM edition includes the following Form library functions that the other
editions do not:
– GetType
– GetIdentifier
– ReadFormFromASPRequest
– WriteFormToASPResponse
© Copyright IBM Corp. 2003, 2006 3
In all other respects, the different editions of the API provide the same
functionality, and use the same memory model for forms.
The API Data Types
IFormNodeP Objects
The functions in the Form Library store forms in memory as a series of linked
nodes. Each node, regardless of its level in the hierarchy, is represented by a
IFormNodeP object.
The functions in the Form Library are responsible for creating and populating
these nodes, and for freeing the memory they occupy.
About Memory Use
The Form methods are responsible for creating and populating these nodes.
Furthermore, once you are done working with a form, you must use the destroy
method on the root node of the form to remove it from memory.
About the API Constants
Several of the Form Library functions accept parameters whose values are
constants (for example, the referenceType parameter of DereferenceEx). All constants
have been defined in the IFS_COM_API type library, and are available by
including that library in your source file, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
4
Overview of the Form Structure
This section provides an overview of an XFDL form as it is represented in memory.
Developers must understand the memory structure of a form to effectively develop
applications using the API.
The Node Structure
When a form is loaded into memory, it is constructed as a series of linked nodes.
Each node represents an element of the form, and together these nodes create a
tree that describes the form. The following diagram illustrates the general
composition of a single node.
Each node within the tree has the following properties:
v Type — For page and item nodes, this describes the type of node, such as
button, line, field, and so on. Page nodes are always of type page.
v Literal — The literal value of the node (for example, a literal string). If the node
has a formula, the result of the formula will be stored here.
v Identifier — The page tag, item tag, option name, or custom name assigned to
the node.
v Compute — The compute assigned to the node (for example, ″field_1.value +
field_2.value″). The result of the compute will be stored in the literal of the
node.
Depending on the node type, some of these properties may be null.
The Node Hierarchy
Every node is part of an overall hierarchy that describes the complete form. This
hierarchy follows a standard tree structure, with the top of the tree being the top
(or root) of the hierarchy.
The diagram on the following page illustrates the typical tree structure for a simple
form.
The elements of the hierarchy, in descending order, are:
v Form — Each form has one form level node. This is the root node of the tree.
v Page — Each form contains pages, which are represented as children of the form
node. Each form has at least two page nodes - one for the globalpage, which
stores the global settings, and one for the first page of the form.
v Item — Each page contains items, which are represented as children of the page
node. An item node is created for each item, including the global item which
stores page settings.
v Option — Each item contains options, which are represented as children of the
item node. An option node is created for each option.
v Argument — Options often contain further settings, or arguments, which are
represented as children of the option node or as children of other argument
© Copyright IBM Corp. 2003, 2006 5
nodes. There may be more than one level of argument node created below an
option node, depending on the option’s settings. The easiest way to access a
particular node in the hierarchy is to use a reference. References allow you to
locate a specific node without first having to locate the parent of that node.
References
References allow you to identify a specific page, item, option, or argument by
providing a ″path″ to that element. This means that you can access an element
directly without having to locate any of its ancestors. The syntax of a reference
follows this general pattern:
page.item.option[argument]
Each element of the reference is constructed as follows:
v Page and Item — Pages and items are identified by their scope identifiers (sid).
For example, Page1 or Field1.
6
v Options — Options are identified by their tag name. For example, value or
itemlocation.
v Arguments — Arguments are identified by their tag name or a zero-based
numeric index. Argument references are always enclosed in brackets. For
example, [1] or [message].
Arguments can also have any depth. For example, you might have an argument
that contains arguments. You can reference additional levels of depth by adding
another bracketed reference. For example, to refer to the first argument in the
first argument of the printsettings option, you could use either [0][0] or the tag
names in brackets, such as [pages][filter].
You can create references to any level of the node hierarchy. For example, the
following table illustrates a number of references starting at different levels of the
form:
Start At
Ref to
Page Ref to Item Ref to Option Ref to Argument
Page Page1 Page1.Field1 Page1.Field1.format Page1.Field1.format[message]
Item — Field1 Field1.format Field1.format[message]
Option — — format format[message]
Argument — — — [message]
Dereferencing
When making a reference to an item node, there may be times when you do not
know which node to reference because it depends on some action from the user of
the form. Consider a situation in which a user selects a cell from a list. Because
you don’t know beforehand which cell the user will choose, it is not possible to
explicitly reference the item node for the chosen cell. In such cases you would use
dereferencing to retrieve the node indirectly.
Essentially, dereferencing allows you to make a dynamic reference that is evaluated
at runtime. This is accomplished by placing the -> symbol to the right of the
dynamic reference.
For example, consider a list item called List1 that has three cells called Cell1, Cell2,
Cell3. If you wanted to access the item node of the cell selected by the user, we
would use the following reference string:
List1.value->
At runtime, the portion of the expression that is to the left of the dereference
symbol is evaluated and replaced. If the user chose the second cell, List1.value
would be evaluated and replaced with:
Cell2
As a result, the item node for Cell2 would be returned.
In some cases, instead of accessing the item node of the chosen cell, you may want
to access one of the cell’s option nodes. Again, dereferencing is used. The reference
string would be:
List1.value->value
As before, the above expression is evaluated at runtime. The expression to the left
of the dereference symbol is evaluated and replaced, just as before. So if the second
Overview of the Form Structure 7
cell was selected, List1.value would be evaluated as Cell2. This value is then
concatenated with the expression to the right of the dereference symbol. This
would produce:
Cell2.value
As a result, the option node for Cell2.value would be returned.
Note: Do not include any spaces before or after the dereference symbol (->).
Namespace in References
References that include options or arguments in any namespace other than XFDL
normally require the inclusion of the namespace prefix in the reference. For
example, if you were referencing ″myOption″ in the ″custom″ namespace, you
would refer to that option as ″custom:myOption″ as shown:
page_1.myItem.custom:myOption
If you are referencing named arguments, you should also use the appropriate
namespace. For example:
page_1.myItem.custom:myOption[custom:myArgument]
However, if you are referencing an argument by index number you do not need to
worry about namespace. All arguments, regardless of namespace, are indexed in
order. For example, if ″myOption″ contained two arguments, the first in the XFDL
namespace and the second in the custom namespace, you would use the following
reference for the second argument:
page_1.myItem.custom:myOption[1]
Note: Page and item references never require a namespace prefix because they are
uniquely identified by their sid.
The null Namespace
In some cases, forms may have no default namespace or may have a default
namespace that is explicitly set to an empty string. In these cases, you can use null
as the prefix for the empty namespace. For example, the following field declares a
default namespace that is empty:
<page sid="Page1">
<field sid="myField" xmlns="">
<value>Test Value</value>
</field>
</page>
In this case, to reference the value of the field, you would use the null prefix as
shown:
Page1.null:myField.null:value
Advanced Information about the Node Structure
When an XFDL form is stored in memory, it exists as a series of nodes that are
linked in a tree structure. As described in “The Node Hierarchy” on page 5, the
tree structure follows this hierarchy: form, page, item, option, and argument.
Within a single branch of the tree, all elements of the same level are treated as
siblings, each of which has a common parent, and each of which may have its own
children.
8
The following example illustrates the node structure of a simple form, and gives a
top-down description of the node structure.
A Sample Hierarchy
The following XFDL code creates the node hierarchy shown in . The result is a
simple form that contains three items (a line and two labels).
<?xml version = "1.0"?>
<XFDL xmlns="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0">
<globalpage sid="global">
<global sid="global"></global>
</globalpage>
<page sid = "PAGE1">
<global sid="global"></global>
<line sid = "REFLINE">
<size>
<width>20</width>
<height>0</height>
</size>
</line>
<label sid = "LABEL1">
<value>Hello</value>
</label>
<label sid = "LABEL2">
<value>World</value>
<itemlocation>
<after>LABEL1</ae>
<expandr2r>REFLINE</expandr2r>
</itemlocation>
</label>
</page>
</XFDL>
The Sample Tree Structure
Each tree begins with the form, or root, node. This node contains no information -
it simply represents the starting point of the tree structure.
Below the form node are the page nodes. In the previous example, there are two
page nodes: ″global″ and ″PAGE1″. The ″global″ page node stores any global
settings that apply to the form while ″PAGE1″ stores the contents of the first form
page. Any additional pages would also be stored as children of the form node.
Below each page node are the item nodes. As illustrated in the previous example,
the first item node for any page is always the ″global″ item. The ″global″ item
stores any page settings that are applied to the items in that page. Each additional
item in the page is stored as a sibling of the global item.
Note: The ″global″ page node will always have one child: the global item. This
global item will always store the XFDL version number used to create the
form, and is also used to store any global settings that are applied to the
form.
Below each item node are the option nodes. Each option node represents an option
setting for that item, such as a background color or font setting.
Below each option node are the argument nodes. These nodes contain the settings
for the parent option. For example, the background color might be set to ″blue″.
Overview of the Form Structure 9
There can be an infinite number and depth of these nodes, depending upon the
number and depth of the settings for that option.
For instance, in the sample form, the size node for ″REFLINE″ has two argument
nodes: one for the width and one for the height. In contrast, the printsettings option
can have multiple argument nodes which themselves have argument nodes as
children. The following is an example of the node structure of the printsettings
option:
<printsettings>
<pages> argument node level I
<filter>omit</filter> argument node level II
<pageref>page2</pageref> argument node level II
</pages>
<dialog> argument node level I
<active>on</active> argument node level II
<orientation>landscape<orientation> argument node level II
<copies>2</copies> argument node level II
</dialog>
</printsettings>
<printsettings>
<pages> argument node level I
<filter>omit</filter> argument node level II
<pageref>page2</pageref> argument node level II
</pages>
<dialog> argument node level I
<active>on</active> argument node level II
<orientation>landscape<orientation> argument node level II
<copies>2</copies> argument node level II
</dialog>
</printsettings>
printsettings Node Structure
orientation
landscape
printsettings
pages
filter
omit
pageref
PAGE2
active
on
dialog
copies
2
Thus, in storing the printsettings option, two levels of argument nodes are created.
The first level describes the number of array elements in the option (two). The
second level gives the arguments for each element.
Due to their potential complexity, pay careful attention to the mapping of
argument nodes.
Note: In cases where an option has multiple elements in an array (for example,
printsettings), there will be a single option node, but a separate argument
node for each element in the array.
Node Properties
There are several levels of nodes in an XFDL form: form (or root), page, item,
option, and argument (which can have an infinite number of levels). Each node has
four properties: literal, type, identifier, and compute. A node does not necessarily
contain information for every property.
For example, a page node can never have values for the compute or literal
properties. And while a value for the user data property is optional, a page node
must always have values for the type and identifier properties.
The following table illustrates what properties may be in use for each node level.
10
Node Property
Level
Form
Page
Item
Option
Argument (at
any level)
Literal Type Identifier Compute
no
no
no
no
no
no
no
no no
no
yes
yes
yes
yes
always
always
always
always
always
yes
yes — node can have that property
always — node always has that property
no — node cannot have that property
Overview of the Form Structure 11
12
Introduction to the Form Library
The Form Library is a collection of functions for developing applications that
manipulate XFDL forms. Using the functions in the Form Library, your
applications can:
v Read and write forms.
v Retrieve information contained in a form’s elements.
v Assign information to the elements of a form.
v Create new elements within a form.
v Remove elements from a form.
v Extract images or enclosures from a form.
v Verify digital signatures.
Essentially, an XFDL form may be thought of as a structured data type, with the
API as the means for accessing this data structure.
© Copyright IBM Corp. 2003, 2006 13
14
Getting Started with the Form Library
This section provides a detailed tutorial to help you understand how to use the
Form Library. By working through the tutorial, you will perform all of the steps
involved in creating a simple application that uses the API functions, including:
v Initializing the Form Library.
v Reading a form into your application.
v Setting and retrieving form data.
v Removing a form from memory.
The sample application in this tutorial reads an input form called CalculateAge.xfd
into memory. It retrieves the user’s birth day, month, and year as well as the
current date from the form. It then places these values into hidden fields in the
form. This triggers the form to compute the user’s age and display the result.
When complete, the application saves the changes made to calculateAge.xfd as a
new form called Output.xfd.
Note: The sample application described in this tutorial is included with the API
and can be found in the folder: <API Program Folder>\Samples\COM\
Form\Demo\Calculate_Age\
The tutorial describes the following tasks:
“Setting Up Your Application”
“Initializing the Form Library” on page 16
“Loading a Form” on page 17
“Retrieving A Value from a Form” on page 17
“Setting a Value in a Form” on page 18
“Writing a Form to Disk” on page 19
“Closing a Form” on page 20
“Compiling Your Application” on page 20
“Testing your Application” on page 20
“Distributing Applications That Use the Form Library” on page 21
Note: Before you can build applications using the Form Library, you must install
the API and set up your development environment. Refer to the IBM
Workplace Forms Server - API Installation and Setup Guide for more
information.
Setting Up Your Application
This example assumes that you are developing a program in Microsoft Visual Basic
using Microsoft Studio. To begin, you must first set up your development
environment to use the API type library.
1. Create a new Visual Basic project.
2. Any project using the API must include the following type library:
v IFS_COM_API.tlb
© Copyright IBM Corp. 2003, 2006 15
To add this to your Visual Basic Project, open the References dialog from the
Project menu and select “InternetForms API”.
3. Set up the rest of your application. This generally includes setting up your
main algorithm and declaring any variables you will need. The following code
sets up the Calculate Age application:
’ Create the Main method for the program.
Sub Main()
’ Declare a number of variables. TheForm represents the form, while the
’ other variables are values we will read from the form.
Dim TheForm As IFormNodeP
Dim BirthYear As Integer
Dim BirthMonth As Integer
Dim BirthDay As Integer
’ The program’s Main consists of a number of calls to other functions.
Initialize
Set TheForm = LoadForm
BirthYear = GetBirthYear(TheForm)
BirthMonth = GetBirthMonth(TheForm)
BirthDay = GetBirthDay(TheForm)
SetBirthYear BirthYear, TheForm
SetBirthMonth BirthMonth, TheForm
SetBirthDay BirthDay, TheForm
SaveForm TheForm
’ Free the memory in which the form was stored.
TheForm.Destroy
End Sub
Initializing the Form Library
All applications that use the API functions must initialize the Form Library to
ensure correct error and memory handling behavior. The sample application does
this in a separate method called Initialize. In turn, Initialize calls the Form Library
function IFSInitialize and passes it the name of the current program.
Define the Initialize function to call the function IFSInitialize. IFSInitialize
initializes the API environment.
Sub Initialize()
Dim DTK As DTK
’ Get the DTK object. You need this call the IFSInitialize function.
Set DTK = CreateObject("PureEdge.DTK")
’ Call DTK.IFSInitialize. DTK is a static class representing the Java
’ API development toolkit. The parameters are:
’ 1. CalculateAge: the name of the application being run.
’ 2. 1.0.0 : the version of the application being run.
’ 3. 2.6.0 : the version of the API being run.
16
’ An exception will be thrown if there is a problem.
DTK.IFSInitialize "CalculateAge", "1.0.0", "2.6.0"
End Sub
Note: For detailed information about the IFSInitialize function, including a
description of its parameters, refer to “IFSInitialize” on page 117.
Loading a Form
Before your program can begin working with a form, you must load it into
memory. CalculateAge does this by defining a LoadForm function to handle these
tasks.
Call ReadForm within the implementation of your loadForm function to read in
the form, calculateAge.xfd.
Function LoadForm() As IFormNodeP
Dim XFDL As XFDL
’ Get the XFDL object. You need this to call the ReadForm function.
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Call XFDL.ReadForm. The parameters are:
’ 1. calculateAge.xfd : indicates the file on the local drive to read
’ the form from.
’ 2. 0 : no special behavior.
’ readForm will return a reference to the root node of the
’ new form structure once it is loaded into memory. An exception
’ will be thrown if there is a problem.
Set LoadForm = XFDL.ReadForm("c:\calculateage.xfd", 0)
End Function
Note: For more information about the ReadForm function, refer to “ReadForm” on
page 152.
Retrieving A Value from a Form
Once you have set up and initialized your application with the API and loaded a
form into memory, your application is ready to start working with the form. The
following code uses GetLiteralByRefEx to get a specific value from the form:
Retrieve the birth date from the form as three separate values: the birth day, birth
month, and birth year. To do this, we will use three separate functions. Each
function uses GetLiteralByRefEx to retrieve one of the values.
Function GetBirthDay(TheForm) As Integer
Dim BDay As String
’ Call IFormNodeP.GetLiteralByRefEx to get the literal information for
’ the PAGE1.BIRTHDAY.value node. An exception will be thrown if
’ there is a problem.
BDay = TheForm.GetLiteralByRefEx(vbNullString, _
"PAGE1.BIRTHDAY.value", 0, vbNullString, Nothing)
’ If a literal value was returned, convert it into an integer value;
’ otherwise, indicate that no value was entered into the field
Getting Started with the Form Library 17
’ and throw an exception.
If (Len(BDay) > 0) Then
GetBirthDay = CInt(BDay)
Else
MsgBox "The birth day was not entered.", vbCritical
Stop
End If
End Function
’ Similar to GetBirthDay
Function GetBirthMonth(TheForm) As Integer
Dim BMonth As String
BMonth = TheForm.GetLiteralByRefEx(vbNullString, _
"PAGE1.BIRTHMONTH.value", 0, vbNullString, Nothing)
If (Len(BMonth) > 0) Then
GetBirthMonth = CInt(BMonth)
Else
MsgBox "The birth month was not entered.", vbCritical
Stop
End If
End Function
’ Similar to getBirthDay()
Function GetBirthYear(TheForm) As Integer
Dim BYear As String
BYear = TheForm.GetLiteralByRefEx(vbNullString, _
"PAGE1.BIRTHYEAR.value", 0, vbNullString, Nothing)
If (Len(BYear) > 0) Then
GetBirthYear = CInt(BYear)
Else
MsgBox "The birth year was not entered.", vbCritical
Stop
End If
End Function
Note: For detailed information about the GetLiteralByRefEx method, including a
description of its parameters, refer to “GetLiteralByRefEx” on page 58.
Setting a Value in a Form
Once a form is loaded into memory, a developer can set the values associated with
any of the item or option nodes located in the form by calling SetLiteralByRefEx.
Change the values of hidden fields in the original form. These hidden fields are
arguments for a compute in the SHOWAGE label that calculates the user’s age. To
do this, we will use three separate functions. Each function uses SetLiteralByRefEx
to set one of the values.
Sub SetBirthDay(BDay As Integer, TheForm As IFormNodeP)
Dim Day As String
18
’ Convert the birthday to a String
Day = CStr(BDay)
’ Call TheForm.SetLiteralByRefEx. The parameters are:
’ 1. vbNullString : reserved. Must be vbNullString.
’ 2. PAGE1.HIDDENDAY.value : the reference to the node.
’ 3. 0 : must be zero.
’ 4. vbNullString : sets the character set to ANSI.
’ 5. Nothing : no namespace node required.
’ 6. Day : the value to assign to the literal.
’ An Exception will be thrown if there is a problem.
TheForm.SetLiteralByRefEx vbNullString, "PAGE1.HIDDENDAY.value", _
0, vbNullString, Nothing, Day
End Sub
’ Similar to SetBirthDay()
Sub SetBirthMonth(BMonth As Integer, TheForm As IFormNodeP)
Dim Month As String
’ Convert the birth month to a String
Month = CStr(BMonth)
’ Set the birth month as a value in the form.
TheForm.SetLiteralByRefEx vbNullString, "PAGE1.HIDDENMONTH.value", _
0, vbNullString, Nothing, Month
End Sub
’ Similar to setBirthDay()
Sub SetBirthYear(BYear As Integer, TheForm As IFormNodeP)
Dim Year As String
’ Convert the birth year to a String
Year = CStr(BYear)
’ Set the birth year as a value in the form.
TheForm.SetLiteralByRefEx vbNullString, "PAGE1.HIDDENYEAR.value", _
0, vbNullString, Nothing, Year
End Sub
Note: For detailed information about SetLiteralByRefEx, including a description of
its parameters, refer to “SetLiteralByRefEx” on page 92.
Writing a Form to Disk
Once you have finished making the desired changes to the form, you should save
it to disk. If you want to retain the original form (calculateAge.xfd), you should
save the modified form under a new name. This program saves the modified form
as Output.xfd.
The following example implements the function SaveForm. This function calls the
API function WriteForm that writes a form to disk.
Getting Started with the Form Library 19
Sub SaveForm(TheForm)
’ Call theForm.writeForm. theForm is the root node of the form to
’ be written. The parameters are:
’ 1. output.xfd : the filename you want to use (you could also use
’ a path here).
’ 2. Nothing : since we do not want to set a triggeritem.
’ 3. 0 : since we do not want to allow the transmit options to work.
’ An exception is thrown if there is a problem.
TheForm.WriteForm "output.xfd", Nothing, 0
End Sub
Note: For detailed information about WriteForm, including a description of its
parameters, refer to “WriteForm” on page 109.
Closing a Form
Next, you must free the memory used by the form itself. This is the last operation
in the main function of the program.
The program’s main method calls the API’s Destroy method to delete TheForm
object.
’ Now that we are done with the form, we can free the memory by
’ calling Destroy. The object, ’TheForm’, is a reference to
’ the root node of the form. This causes the root node and all
’ of its children (the complete form) to be deleted from memory.
TheForm.Destroy
End Sub
Note: For detailed information about Destroy, including a description of its
parameters, refer to “Destroy” on page 44.
Compiling Your Application
Once you have generated the source files for your application, you must compile
the source code.
v Use an appropriate compiler that is supported by this API to compile your files.
Refer to the IBM Workplace Forms Server - API Installation and Setup Guide for
more information about compatible development environments.
v Before building your application you should have a source file that represents
your application. After compiling the file you will have a file an executable (or
class file) with the same name.
v The details of compiling your source code are not included in this manual.
Consult your development environment’s documentation for specific information
on how to use your compiler.
v Make sure that the compiler uses the -I option when searching the directory
containing the API include files.
Testing your Application
Use the sample form that accompanies the API to test the Calculate Age
application.
20
1. Copy the file calculateAge.xfd to the folder containg your application. The file
is located in the following folder:
<API Program folder>\Samples\COM\Form\Demo\Calculate_Age\
2. Open the form in the Viewer to see the original settings.
3. Run the application that you have just created.
4. A new file will be created called Output.xfd.
Note: To view the forms provided with this API, you must have a licensed or
evaluation copy of the IBM Workplace Forms Viewer installed.
Distributing Applications That Use the Form Library
If you distribute applications that use the Form Library, you will also need to
distribute a number of API files. Refer to the IBM Workplace Forms Server - API
Installation and Setup Guide for information about distributing applications that use
the Form Library.
Summary
By working through this section you have successfully built the Calculate Age
application. In the process, you have learned how to initialize, compile, and test
form applications using the following methods from the Form Library:
v IFSInitialize
v ReadForm
v GetLiteralByRefEx
v SetLiteralByRefEx
v WriteForm
v Destroy
The source code for the Calculate Age application is included with this API and
can be found in the following folder:
<API Program folder>\Samples\COM\Form\Demo\Calculate_Age\
To view the forms provided with the sample application, you must have a copy of
the Viewer installed.
Note: The sample files provided are compatible with the Microsoft Visual Basic 6.0
development environment. For more information about compatible
development environments for the API refer to the IBM Workplace Forms
Server - API Installation and Setup Guide.
Getting Started with the Form Library 21
22
Form Library Quick Reference Guide
This section provides detailed information about the Form Library. The available
functions are divided into the following categories:
v “The Certificate Functions” on page 29.
v “The FormNodeP Functions” on page 35.
v “The Hash Functions” on page 113.
v “The Initialization Functions” on page 117.
v “The LocalizationManager Functions” on page 123.
v “The SecurityManager Functions” on page 135.
v “The Signature Functions” on page 139.
v “The XFDL Functions” on page 147.
Within each section, the functions are presented alphabetically.
Form Library Functions
The Form Library includes the following functions:
Function Type Description Functions
Certificate The Certificate function
gets information from
digital certificates.
GetBlob
GetDataByPath
GetIssuer
FormNodeP The FormNodeP
functions create and
populate nodes and free
memory.
AddNamespace
CreateCell
DeleteSignature
DereferenceEx
Destroy
Duplicate
EncloseFile
EncloseInstance
© Copyright IBM Corp. 2003, 2006 23
Function Type Description Functions
FormNodeP
(continued)
The FormNodeP
functions create and
populate nodes and free
memory.
ExtractFile
ExtractInstance
ExtractXFormsInstance
GetAttribute
GetAttributeList
GetCertificateList
GetChildren
GetFormVersion
GetIdentifier
GetLiteralEx
GetLiteralByRefEx
GetLocalName
GetNamespaceURI
GetNamespaceURIFromPrefix GetNext
GetNodeType
GetParent
GetPrefix
GetPrefixFromNamespaceURI
GetPrevious
GetReferenceEx
GetSecurityEngineName
GetSigLockCount
GetSignature
GetSignatureVerificationStatus
GetType
IsSigned
IsXFDL
24
Function Type Description Functions
FormNodeP
(continued)
The FormNodeP
functions create and
populate nodes and free
memory.
RemoveEnclosure
ReplaceXFormsInstance
SetActiveForComputationalSystem
SetAttribute
SetFormula
SetLiteralEx
SetLiteralByRefEx
SignForm
ValidateHMACWithSecret
ValidateHMACWithHashedSecret
VerifyAllSignatures
VerifySignature
WriteForm
WriteFormToASPResponse
XMLModelUpdate
Hash The Hash functions hash
data.
Hash
Initialization The Initialization
functions initialize the
API.
IFSInitialize
LocalizationManager The LocalizationManager
functions control which
locale (language) the API
uses.
GetCurrentThreadLocale
GetDefaultThreadLocale
SetCurrentThreadLocale
SetDefaultLocale
SecurityManager The SecurityManager
functions provide hashing
algorithms.
LookupHashAlgorithm
Signature The Signature functions
get information from
signatures.
GetDataByPath
GetSigningCert
XFDL The XFDL functions
create the root nodes of
XFDL forms and handle
administrative tasks
related to the API.
Create
GetEngineCertificateList
IsDigitalSignaturesAvailable
ReadForm
ReadFormFromASPRequest
Form Library Quick Reference Guide 25
About the Function Descriptions
The functions in this reference guide are listed according to the functionality they
provide and are described using the following format:
v Description: Provides a general description of what the function does.
v Function: Lists the function’s signature and type of value returned (if any).
v Parameters: Lists and describes each parameter in detail.
v Returns: Indicates what value is returned by the function.
v Notes: Provides additional information to help you use the function.
v Example: Provides sample code that uses the function in question.
Note: All sample code for the COM API is written in VBScript, and assumes it
is running as part of an ASP page. However, you can use any COM
compliant language when writing your own programs.
Using Signatures with the Form Library
Computed options often contain their current computed value. If this value is
signed, it will not change, even if something in the form changes that would
normally trigger the compute.
The literal value is stored as simple character data in the computed option, as
shown below:
<field sid="FIELD1">
<value compute="page1.nameField.value">Jane E. Smith</value>
</field>
The node structure for this value option is:
Page1.nameField.value
field FIELD1
Jane E. SmithJane E. Smith
value
The Viewer sets this literal value when a form is signed, submitted, or saved (and
discards any old value if necessary). When ReadForm is invoked, the current value
(cval) is set and cannot be changed. Because a digitally signed formula never fires
after being signed, the current value for the option is always the same - and
therefore it is possible to reference the option and get the signed literal value.
About Errors
The COM API reports errors in one of two ways, depending on the programming
language you are using. If your programming language supports structured errors,
the COM API will throw exceptions. Otherwise, the COM API will report errors in
the HResult, and you will have to handle those errors manually.
26
About Output Parameters
When using VBScript, the COM interface does not properly match output
parameters with variant data types. This means that any function requiring an
output parameter will not function properly. If you are programming in VBScript,
set all output parameters to null rather than using a variable.
The nulls required under VBScript are:
v Nothing — Used for all objects.
v vbNullString — Used for all strings.
v vbNull — Used for other data types. vbNull is equivalent to the constant ″1″,
and is not declared by default in VBScript. Rather than declaring a constant
variable, you should use ″1″ in all cases.
Form Library Quick Reference Guide 27
28
The Certificate Functions
The Certificate functions allow you to work with Certificate objects.
v To use the Certificate functions you must import the IFS_COM_API type library,
as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
GetBlob
Description
This function extracts a binary long object (Blob). This Blob is a DER-encoded
certificate.
Function
Function GetBlob(
theStatus As Long
) As Variant
Parameters
Expression Type Description
theStatus Long A long that is set with the status of the
operation. This will be one of the following:
SUSTATUS_OK — The operation was
successful.
SUSTATUS_CANCELLED — the operation was
cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the
operation required user input, but could not
receive it (for example, it was run on a server
with no user).
Returns
The Blob as a variant containing an array of bytes.
Example
The following function extracts the Blob from a certificate, checks the status to
make sure the operation was successful, then returns the Blob.
Sub extractBlob(TheCert)
Dim TheBlob ’ Variant
’ Get the Blob from the certificate
TheBlob = TheCert.GetBlob(1) ’ vbNull
’ Call the ProcessBlob function to process the certificate Blob. Note
’ that this is not an API function, but rather a function you would
© Copyright IBM Corp. 2003, 2006 29
’ write to do some processing, such as writing the Blob to disk.
ProcessBlob(TheBlob);
End Sub
GetDataByPath
Description
This function retrieves a piece of data from a certificate object.
Function
Function GetDataByPath(
dataPath As String,
tagData As Boolean,
encoded As Boolean
) As String
Parameters
Expression Type Description
thePath String The path to the data you want to retrieve.
See the Notes section below for more
information on data paths.
tagData Boolean True if the path should be prepended to
the data, or False if not. If the path is
prepended, an equals sign (=) is used as a
separator.
For example, suppose the path is ″Signing
Cert: Issuer: CN″ and the data is ″IBM″. If
True, the path will be prepended,
producing ″CN=IBM″. If False, the path
will not be prepended, and the result will
be ″IBM″.
encoded Boolean True if the return data is base 64 encoded,
or False if not. The function returns binary
data in base 64 encoding.
Notes
About Data Paths
Data paths describe the location of information within a certificate, just like file
paths describe the location of files on a disk. You describe the path with a series of
colon separated tags. Each tag represents either a piece of data, or an object that
contains further pieces of data (just like directories can contain files and
subdirectories).
For example, to retrieve the version of a certificate, you would use the following
data path:
version
However, to retrieve the subject’s common name, you first need to locate
thesigning certificate, then the subject, then the common name within the subject,
as follows:
30
SigningCert: Subject: CN
Some tags may contain more than one piece of information. For example, the
issuer’s organizational unit may contain a number of entries. You can either
retrieve all of the entries as a comma separated list, or you can specify a specific
entry by using a zero-based element number.
For example, the following path would retrieve a comma separated list:
Issuer: OU
While adding an element number of 0 would retrieve the first organizational unit
in the list, as shown:
Issuer: OU: 0
Certificate Tags
The following table lists the tags available in a certificate object:
Tag Description
Subject The subjects distinguished name. This is an object that contains
further information, as detailed in Distinguished Name Tags.
Issuer The issuer’s distinguished name. This is an object that contains
further information, as detailed in Distinguished Name Tags.
IssuerCert The issuer’s certificate. This is an object that contains the complete
list of certificate tags.
Engine The security engine that generated the certificate. This is an object
that contains further information, as detailed in Security Engine Tags.
Version The certificate version.
BeginDate The date on which the certificate became valid.
EndDate The date on which the certificate expires.
Serial The certificates serial number.
SignatureAlg The signature algorithm used to sign the certificate.
PublicKey The certificates public key.
FriendlyName The certificates friendly name.
Distinguished Name Tags
The following table lists the tags available in a distinguished name object:
Tag Description
CN The common name.
E The e-mail address.
T The title.
O The organization.
OU The organizational unit.
C The country.
L The locality.
ST The state.
All The entire distinguished name.
The Certificate Functions 31
Security Engine Tags
The following table lists the tags available in the security engine object:
Tag Description
Name The name of the security engine used by the server.
Help The help text for the security engine.
HashAlg A hash algorithm supported by the security engine.
Returns
A string containing the certificate data (null if no data is found), or throws an
exception if an error occurs.
Example
The following function uses DereferenceEx to locate a signature button in the
form. It then calls GetCertificateList to get a list of valid certificates for that
button. The function then loops through the available certificates, using
GetDataByPath to check the common name of each certicate. When it finds the
certificate with the common name of ″TJones″, it calls SignForm and uses that
certificate to sign the form.
Sub ApplySignature(Form)
Dim SigNode, SigObject ’ objects
Dim TheCerts ’ CertificateList
Dim CommonName ’ String
Dim Cert ’ ICertificate
’ Get the SignatureButton node
Set SigNode = Form.DereferenceEx(vbNullString, _
"PAGE1.SignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get available certificates for that button
Set TheCerts = SigNode.GetCertificateList(vbNullString, 1) ’vbNull
’ Test each of the available certificates to see if it has a common
’ name of "TJones". If it does, use that certificate to sign
’ the form.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
Response.Write CommonName & vbCrLf
If CommonName = "TJones" Then
Set SigObject = SigNode.SignForm(TheCerts(1), Nothing, 1)
’ vbNull
End If
Next
End Sub
32
GetIssuer
Description
This function extracts the issuer certificate from the certificate provided.
Function
Function GetIssuer(
theStatus As Long
) As Certificate
Parameters
Expression Type Description
theStatus Long A long that is set with the status of the operation.
This will be one of the following:
SUSTATUS_OK — The operation was successful.
SUSTATUS_CANCELLED — the operation was
cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the operation
required user input, but could not receive it (for
example, it was run on a server with no user).
Returns
The issuer certificate.
Example
The following example gets the signing certificate from a signature object, then
iterates through the certificate issuers until it reaches the end of the chain. During
the iteration, each certificate is passed to a function that processes them.
Sub processCertChain(TheSig)
Dim TheCert, IssuerCert ’ ICertificate
’ Get the signing certificate from the signature
Set TheCert = TheSig.GetSigningCert()
’ Loop through the certificate chain, passing each certificate to the
’ ProcessCert function. The loop ends when the issuer certificate is
’ Nothing.
Do While (Not(TheCert Is Nothing))
’ Pass the certificate to the ProcessCert function. Note that
’ this is not an API function, but rather a function you would
’ write to process the certificate in some way.
ProcessCert(TheCert)
’ Get the issuer certificate from the TheCert
Set IssuerCert = TheCert.GetIssuer(1) ’ vbNull
’ Assign theCert to equal the issuerCert for next iteration of the
’ loop.
The Certificate Functions 33
Set TheCert = IssuerCert
Loop
End Sub
34
The FormNodeP Functions
The FormNodeP functions apply to particular instances of a form and the items in
that form.
v Each node in a form, regardless of its level in the node hierarchy, is represented
by a IFormNodeP object. For more information about the node structure of
XFDL forms refer to “Overview of the Form Structure” on page 5.
v To use the FormNodeP functions you must import the IFS_COM_API type
library, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
FormNodeP Constants
The following table lists the constants that are used by the IFormNodeP functions
along with a short description of each constant:
Named Constants Description
UFL_DS_CERTEXPIRED The certificate has expired.
UFL_DS_CERTNOTFOUND The certificate was not found.
UFL_DS_CERTNOTTRUSTED The certificate is no longer trusted.
UFL_DS_CERTREVOKED The certificate has been revoked.
UFL_DS_F2MATCHSIGNER The name in the form did not match the
name in the signature.
UFL_DS_HASHCOMPFAILED The hash of the document did not match
the hash in the signature.
UFL_DS_ISSUERNOTFOUND The issuer could not be found.
UFL_DS_ISSUERSIGFAILED The verification of the issuer’s certificate
failed.
UFL_DS_SIGNATUREALTERED The signature has been altered.
UFL_DS_UNEXPECTED Generic error.
addNamespace
Description
This function adds a namespace declaration to the node it is called on. Each
namespace is defined in the form by a namespace declaration, as shown:
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
Each namespace declaration defines both a prefix and a URI for the namespace. In
this sample, the prefix for the XFDL namespace is xfdl and the URI is
http://www.ibm.com/xmlns/prod/XFDL/7.0.
Tags within the form are assigned specific namespaces by using the defined prefix.
For example, to declare that an option was in the custom namespace you would
use the prefix custom as shown:
© Copyright IBM Corp. 2003, 2006 35
<field sid="testField">
<custom:custom_option>value</custom:custom_option>
</field>
Function
Sub AddNamespace(
theURI As String,
thePrefix As String)
Parameters
Expression Type Description
theURI String The namespace URI. For example:
http://www.ibm.com/xmlns/prod/XFDL/7.0
thePrefix String The prefix for the namespace. For example, xfdl.
Returns
Nothing or throws an exception if an error occurs.
Example
The following function adds a custom namespace to a form and then adds a custom
option to the global item. First, the function uses AddNamespace to add the
custom namespace to the form. It then uses DereferenceEx to locate the global item
on the form’s global page. Finally, it uses Create to add a custom option to the
global item.
Sub AddCustomNamespace(Node)
Dim TempNode, XFDL ’ objects
Set TempNode = Node
’ Add the Custom namespace to the form
TempNode.AddNamespace"http://www.ibm.com/xmlns/prod/XFDL/Custom", "custom"
’ Locate the global item in the global page
Set TempNode = TempNode.DereferenceEx(vbNullString, "global.global", _
0, UFL_ITEM_REFERENCE, Nothing)
’ Create an XFDL object so that we can use the create function
Set XFDL = CreateObject("Workplace_Forms.xfdl_XFDL")
’ Create a "status" option in the custom namespace as a child of the
’ global item.
Set TempNode = XFDL.Create(TempNode, UFL_APPEND_CHILD, vbNullString, _
"Processed" , vbNullString, "custom:status")
End Sub
36
CheckValidFormats
Description
This function checks the format of all items in the form and returns the number of
items whose format is invalid. You can also set the function to create a list of the
invalid items.
This function does not support XForms nodes.
Function
Function CheckValidFormats() As Boolean
Parameters
There are no parameters for this function.
Returns
An array of nodes that represent items with invalid formats.
Example
The following function walks through the form and uses CheckValidFormats to
determine which nodes have the correct format. This function assumes that you are
passing in the root node of the form.
Sub CheckFormats
Dim theForm ’ object
Dim invalidItems ’ IFormNodePList
Dim theItem ’ IFormNodeP
Dim theReference ’ String
invalidItems = theForm.checkValidFormats();
If invalidItems == Nothing Then
Response.Write("All the items have valid formats."
Else
For Each theItem in invalidItems
theReference = theItem.GetReferenceEx(vbNullString, Nothing, _
Nothing, False)
Response.Write("The item "theReference" has an invalid format".)
End If
End Sub
createCell
Description
Use this function to create a new cell item for a combobox, list, or popup. CreateCell
adds one new cell to a specific group on a specific page in the form. Note that this
function can only assign a name to the new cell; it cannot set the cell’s value. To set
the value of a cell, you must use the SetLiteralByRefEx function.
This function is called from a page level node, and creates the new cell in that
page. Note that you cannot call this function from the global page node.
The FormNodeP Functions 37
Function
Function CreateCell(
theCellName As String,
theGroupName As String
) As IFormNodeP
Parameters
Expression Type Description
theCellName String The name of the new cell being created.
theGroupName String The name of the group option to which
the new cell will be added.
Returns
An IFormNodeP containing the new cell or throws an exception if an error occurs.
Example
The following function adds three cells to a form. First, the function uses
DereferenceEx to locate the PAGE1 node. Next, the function calls CreateCell to
create a new cell on that page and SetLiteralByrefEx to set the value of the new
cell. The function then repeats these steps to create two more cells on that page.
Sub AddCells(Form)
Dim PageNode, CellNode ’ object
Set PageNode = Form
Set PageNode = PageNode.DereferenceEx(vbNullString, "PAGE1", 0, _
UFL_PAGE_REFERENCE, Nothing)
Set CellNode = PageNode.CreateCell("RedCell", "AvailableColors")
CellNode.SetLiteralByRefEx vbNullString, "PAGE1.RedCell.value", 0, _
vbNullString, Nothing, "Red"
Set CellNode = PageNode.CreateCell("BlueCell", "AvailableColors")
CellNode.SetLiteralByRefEx vbNullString, "PAGE1.BlueCell.value", 0, _
vbNullString, Nothing, "Blue"
Set CellNode = PageNode.CreateCell("GreenCell", "AvailableColors")
CellNode.SetLiteralByRefEx vbNullString, "PAGE1.GreenCell.value", 0, _
vbNullString, Nothing, "Green "
End Sub
DeleteSignature
Description
This function deletes the specified digital signature in the form. For security
reasons, the form must meet certain criteria before this is allowed. None of the
following should be locked by another signature: the signature, its descendants, the
associated signature button, and its signer option. If these criteria are met, then the
signature’s locks are removed, and the signature item is deleted. Then, and the
signer of the associated signature button is set to empty (″″).
38
Function
Sub DeleteSignature(
signatureItem As IFormNodeP)
Parameters
Expression Type Description
signatureItem IFormNodeP The signature node to delete.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Notes
If the signature item contains a layoutinfo option, DeleteSignature will not remove
the entire signature from the form. Instead, the signature item and the layoutinfo
option will remain. To completely delete the signature item, you must delete the
remaining nodes manually by using Destroy to delete the signature item.
Example
The following function checks to see the signature in the form is valid. First, the
function uses DereferenceEx to locate the signature button. It then uses
GetLiteralByRefEx to get the name of the signature item, and uses another
DereferenceEx to locate that item. Next, it uses VerifySignature to determine
whether the signature is valid. If so, it return the string ″Valid″. If not, it uses
DeleteSignature to delete the signature and returns the string ″Invalid″.
Function CheckSignature(Form)
Dim TempNode, SigNode ’ objects
Dim SigStatus ’ Integer
Dim SigItemRef ’ Strings
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.SignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get a reference to the signature item from the signature option
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Verify the signature
SigStatus = Form.VerifySignature(SigNode, vbNullString, False)
’ If the signature is not verified, then delete the signature and set
’ the return code to "Invalid". Otherwise, set the return code to
’ "Valid".
If (Not(SigStatus = UFL_DS_OK)) Then
The FormNodeP Functions 39
TempNode.DeleteSignature SigNode
CheckSignature = "Invalid"
Else
CheckSignature = "Valid"
End If
End Function
DereferenceEx
Description
Use this function to locate a particular IFormNodeP, to locate a cell in a particular
group, or to locate a data item in a particular datagroup. The node that this
function operates on is used as the starting point of the search.
Note: It is not necessary to call this function when you are using XForms. The
ReplaceXFormsInstance and ExtractXFormsInstancefunctions perform this
task automatically.
Function
Function DereferenceEx(
theScheme As String,
theReference As String,
theReferenceCode As Long,
referenceType As Long,
theNSNode As IFormNodeP
) As IFormNodeP
Parameters
Expression Type Description
theScheme String Reserved. This must be null.
theReference String The reference string.
theReferenceCode Long Reserved. This must be 0.
40
Expression Type Description
referenceType Long One of the following constants:
UFL_OPTION_REFERENCE
UFL_ITEM_REFERENCE
UFL_PAGE_REFERENCE
UFL_ARRAY_REFERENCE
UFL_GROUP_REFERENCE
UFL_DATAGROUP_REFERENCE
If it is an option or argument reference, bitwise
OR ( | ) with one of:
UFL_SEARCH
UFL_SEARCH_AND_CREATE
If it is a group or datagroup reference, bitwise
OR ( | ) with one of:
UFL_FIRST
theNSNode IFormNodeP A node that is used to resolve the namespaces
in theReference parameter (see the note about
namespace below). Use null if the node that
this function is operating on has inherited the
necessary namespaces.
Returns
The IFormNodeP defined by the reference string or null if the referenced node
does not exist and UFL_SEARCH_AND_CREATE is not specified. On error, the
function throws an exception.
Notes
IFormNodeP
Before you decide which IFormNodeP to use this function on, be sure you
understand the following:
1. The IFormNodeP supplied can never be more than one level in the hierarchy
above the starting point of the reference string. For example, if the reference
string begins with an option, then the IFormNodeP can be no higher in the
hierarchy than an item.
2. If the IFormNodeP is at the same level or lower in the hierarchy than the
starting point of the reference string, the function will attempt to locate a
common ancestor. The function will locate the ancestor of the IFormNodeP that
is one level in the hierarchy above the starting point of the reference string. The
function will then attempt to follow the reference string back down through the
hierarchy. If the reference string cannot be followed from the located ancestor
(for example, if the ancestor is not common to both the IFormNodeP and the
reference string), the function will fail. For example, given a IFormNodeP that
The FormNodeP Functions 41
represents field_1 and a reference of field_2, the function will access the page
node above field_1, and will then try to locate field_2 below that node. If the
two fields were not on the same page, the function would fail.
3. DereferenceEx does not support the XForms scheme.
Creating a Reference String
For general information about creating a reference string, see “References” on page
6.
Reference strings for groups or datagroups follow this format:
page.group or page.datagroup
In both cases, the page component is optional, and is only required if you want to
search a different page than the one containing your reference node.
For example, to refer to the ″State″ group of cells on PAGE1 of the form, you
would use:
PAGE1.State
Locating Cells or Data Items
If you want to locate a cell or a data item, you must perform a bitwise OR with
UFL_FIRST or UFL_NEXT. UFL_FIRST will locate the first cell or data item in the
page. UFL_NEXT will locate the next cell or data item. This allows you to loop
through all the cells or data item on a page until you have found the one you
want.
Note that groups and datagroups are limited to a single page, and that your search
will likewise be limited to a single page.
Creating a Node
For an option or argument reference, you can have the library create a node that
does not exist. To do so, perform a bitwise OR of UFL_SEARCH_AND_CREATE to
the referenceType parameter; otherwise, perform a bitwise OR of UFL_SEARCH to
the referenceType variable and the function will return null if the node does not
exist.
Determining Namespace
In some cases, you may want to use the DereferenceEx function to locate a node
that does not have a globally defined namespace. For example, consider the
following form:
<label sid="Label1">
<value>Field1.processing:myValue</value>
</label>
<field sid="Field1" xmlns:processing="URI">
<value></value>
<processing:myValue>10<processing:myValue>
</field>
In this form, the processing namespace is declared in the Field1 node. Any elements
within Field1 will understand that namespace; however, elements outside of the
scope of Field1 will not.
42
In cases like this, you will often start your search at a node that does not
understand the namespace of the node you are trying to locate. For example, you
might want to locate the node referenced in the value of Label1. In this case, you
would first locate the Label1 value node and get its literal. Then, from the Label1
value node, you would attempt to locate the processing:myValue node as shown:
Label1Node.DereferenceEx(vbNullString, "Field1.processing:myValue", 0,
UFL_OPTION_REFERENCE, vbNullString)
In this example, the DereferenceEx function would fail. The function cannot
properly resolve the processing namespace because this namespace is not defined
for the Label1 value node. To correct this, you must also provide a node that
understands the processing namespace (in this case, any node in the scope of Field1)
as the last parameter in the function:
Label1Node.DereferenceEx(vbNullString, "Field1.processing:myValue", 0,
UFL_OPTION_REFERENCE, Field1Node)
Example
The following example adds a label to a form. A node is passed into the function,
which then uses GetLiteralByRefEx to read the value of a field. The function then
uses DereferenceEx to locate the field node, and creates a label node as a sibling
using Create. Finally, the function creates a value for the new label node using
SetLiteralByRef.
Sub AddLabel(Form)
Dim TempNode, XFDL ’ objects
Dim Name ’ strings
Set TempNode = Form
’ Get the value of the NameField.value option node
Name = TempNode.GetLiteralByRefEx(vbNullString, _
"PAGE1.NameField.value", 0, vbNullString, Nothing)
’ Locate the NameField item node in the first page of the form
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameField", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get an XFDL object
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Create a label. This label is created as a sibling of the NameField,
’ and is named NameLabel.
Set TempNode = XFDL.Create(TempNode, UFL_AFTER_SIBLING, "label", _
vbNullString, vbNullString, "NameLabel")
’ Create a value option for the label. This option is assigned the
’ value of Name (as read from the field)
TempNode.SetLiteralByRefEx vbNullString, "value", 0, vbNullString, _
Nothing, Name
End Sub
The FormNodeP Functions 43
Destroy
Description
This function destroys the indicated IFormNodeP. All children of the specified
IFormNodeP are also destroyed.
Function
Sub Destroy()
Parameters
There are no parameters for this function.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Notes
Digital Signatures
You cannot destroy a signed item, except in the case of destroying an entire signed
form. Destroying a signed item breaks the digital signature, resulting in an
exception.
Example
The following function uses GetChildren and GetNext to walk through an entire
form and deletes all information that is not in the XFDL namespace. The function
uses IsXFDL to determine which nodes are in the XFDL namespace. Note that the
function assumes that you are passing the root node of the form on the first call.
Subsequent calls occur through recursion, which may provide any level of node.
Sub DeleteCustomInfo(Node)
Dim MainNode, TestNode ’ objects
Dim TempInt
’ Set the MainNode to be the child of the provided node.
Set MainNode = Node.GetChildren
’ Use recursion to step through each node in the form. This routine
’ walks to the last node in each page, then traverses back up the tree,
’ deleting nodes that are not in the XFDL namespace as it goes.
Do While (Not(MainNode Is Nothing))
Set TestNode = MainNode.getNext
DeleteCustomInfo(MainNode)
Set MainNode = TestNode
Loop
’ Check to see if the node passed to the routine is in the XFDL
’ namespace. If not, delete the node.
If Node.isXFDL = False Then
Node.Destroy
End If
End Sub
44
Duplicate
Description
This function makes a copy of a node. The duplicate node can be attached to any
other node as either a sibling or a child, or can be stored as a separate node
structure (that is, as a separate form). The new node can also be assigned a new
identifier, as indicated by the theIdentifier parameter. All of the properties of the
original node are duplicated, including any children and any namespace settings.
Note: If you duplicate a node that is not in the XFDL namespace, the namespace is
copied as part of the duplicated node, but is not set globally.
Function
Function Duplicate(
baseNode As IFormNodeP,
where As Long,
theIdentifier As String
) As IFormNodeP
Parameters
Expression Type Description
baseNode IFormNodeP The formNodeP to attach the new copy to. If null,
then origNode is used as the baseNode.
where Long A constant that describes the location in relation to
the supplied ’baseNode’ in which the new node
should be placed. Can be one of:
UFL_APPEND_CHILD — adds the new node as the
last child of the ’baseNode’.
UFL_AFTER_SIBLING — adds the new node as a
sibling of the ’baseNode’, placing it immediately after
that node in the form structure.
UFL_BEFORE_SIBLING — adds the new node as a
sibling of the ’baseNode’, placing it immediately
before that node in the form structure.
UFL_ORPHAN — copies the node to a new form
structure, effectively creating a separate form.
theIdentifier String A new identifier for this node. If null, the same
identifier that was on the original node is used.
Returns
The duplicate node or throws an exception if an error occurs.
Example
The following function duplicates a page in the form, including all of the items on
the page. First, the function uses DereferenceEx to locate the PAGE2 node and
then the PAGE3 node. Next, the function uses Duplicate to create a copy of the
PAGE2 node and place it after the PAGE3 node.
The FormNodeP Functions 45
Sub DuplicatePage(Form)
Dim CopyNode, DestinationNode ’ objects
Set CopyNode = Form
Set DestinationNode = Form
’ Locate the page 2 node. This is the node that will be copied.
Set CopyNode = CopyNode.DereferenceEx(vbNullString, "PAGE2", 0, _
UFL_PAGE_REFERENCE, Nothing)
’ Locate the last page node. The copy will be inserted to the right
’ of this node in the form structure. In other words, the copy will
’ become the last page.
Set DestinationNode = DestinationNode.DereferenceEx(vbNullString, _
"PAGE3", 0, UFL_PAGE_REFERENCE, Nothing)
’ Duplicate the page 2 node, inserting it after the page 3 node. The
’ new page will be named PAGE4.
Set CopyNode = CopyNode.Duplicate(DestinationNode, UFL_AFTER_SIBLING,_
"PAGE4")
End Sub
EncloseFile
Description
This function encloses a file in a form. The file must be accessible on the local
computer. The IFormNodeP may refer to either a page node or an item node. If the
IFormNodeP is a page node, the function creates a data item in that page to
contain the enclosure. If the IFormNodeP is an item node, it must be a data item,
and the function encloses the file in that node.
The file is enclosed using base64-gzip encoding.
Function
Function EncloseFile(
theFile As String,
mimeType As String,
dataGroup As String,
identifier As String
) As IFormNodeP
Parameters
Expression Type Description
theFile String The path to the file on the local drive to enclose.
mimeType String The MIME type of the file. If null, the library will
attempt to find a suitable MIME type for the file.
dataGroup String The data group to which this file should belong. If
the aNode parameter is a page node, you must
provide this parameter. If aNode parameter is an
item node, you may use null to keep the current
datagroup option or provide a different value to
overwrite the option.
46
Expression Type Description
theIdentifier String The identifier to assign to the new data item if one
is created. If null, either the current name is used
or a unique name is automatically generated for
the new data item.
Returns
The IFormNodeP of the item that contains the enclosure or throws an exception if
an error occurs.
Example
The following function encloses a file in a form. The function receives a form, uses
DereferenceEx to locate the PAGE2 node in the form, and then uses EncloseFile to
enclose a text file in the Notices datagroup. The file is stored in a data item named
PersonnelNotice.
Sub AttachFile(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Locate the PAGE2 node.
Set TempNode = TempNode.DereferenceEx(vbNullString, "PAGE2", 0, _
UFL_PAGE_REFERENCE, Nothing)
’ Create an enclosure in this page. The enclosure is stored in a data
’ item called PersonnelNotice, is linked to the Notices datagroup, and
’ encloses a text file from the local drive called Notice.txt.
Set TempNode = TempNode.EncloseFile("c:\Notice.txt", "text/plain", _
"Notices", "PersonnelNotice")
End Sub
EncloseInstance
Description
This function modifies one instance in the data model, either updating information
or appending information. Note that the form must have an existing data model.
Call this function on the root node of the form or an XML instance node.
Note: Use caution when calling this function. It can be used to overwrite signed
instance data.
Function
Sub EncloseInstance(
theInstanceID As String,
theFile As String,
theFlags As Long,
theScheme As String,
theRootReference As String,
theNSNode As IFormNodeP,
replaceNode As Boolean)
The FormNodeP Functions 47
Parameters
Expression Type Description
theInstanceID String The ID of the instance node to create or
replace. This is defined by the id attribute of
that node, and is case sensitive.
If theNode parameter is the instance node you
want to replace, set this parameter to null.
theFile String The path to the file on the local drive that
contains the XML instance.
theFlags Long Reserved. Must be 0.
theScheme String Reserved. Must be null.
theRoot Reference String A reference to the node you want to replace
or append children to. This reference is
relative to the instance node.
Use null to default to the instance node.
theNSNode IFormNodeP A node that inherits the namespaces used in
the reference. This node defines the
namespaces for the function. Use null if the
node that this function is operating on has
inherited the necessary namespaces.
replaceNode Boolean If True, the node specified by theRootReference
is replaced with data. If False, the data is
appended as the last child of theRootReference
node.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Example
The following example shows a function that takes the root node of a form and
updates the XML instance called ″data″.
Sub UpdateDataInstance(Form)
Form.EncloseInstance "Test", "c:\DataInstance.txt", 0, vbNullString, _
vbNullString, Nothing, False
End Sub
ExtractFile
Description
This function will extract an enclosure contained in a node and save it to a file on
the local computer. Note that this function does not remove the enclosure from the
form.
Function
Sub ExtractFile(
theFile As String)
48
Parameters
Expression Type Description
theFile String The path showing where to store the file on the
local drive. Any existing file will be overwritten.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Example
The following function extracts an attachment from a form and saves it to disk.
First, the function uses DereferenceEx to locate the data item containing the
attachment, then it uses ExtractFile to write the attachment to a file on the local
drive.
Sub SaveAttachment(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Locate the PAGE3.DATA1 item, which contains the enclosure.
Set TempNode = TempNode.DereferenceEx(vbNullString, "PAGE3.DATA1", _
0, UFL_ITEM_REFERENCE, Nothing)
’ Extract the enclosure from the data item and save it to disk as
’ c:\Review1.doc
TempNode.ExtractFile "c:\Review1.doc"
End Sub
ExtractInstance
Description
This function copies an instance from a form’s XML model to a file. Note that this
function does not remove the instance from the form.
Call this function on the root node of the form or an XML instance node.
Function
Sub ExtractInstance(
theInstanceID As String,
theFilter As IFormNodeP,
includeNamespaces As String,
theFile As String,
theFlags As Long,
theScheme As String,
theRootReference As String,
theNSNode As IFormNodeP)
The FormNodeP Functions 49
Parameters
Expression Type Description
theInstanceID String The ID of the instance node to extract. This is
defined by the id attribute of that node.
If theNode parameter is the instance node you
want to extract, set this parameter to .
theFilter IFormNodeP An item in the form, such as a button or cell,
that defines the filtering for the instance.
Filtering of elements is controlled by the
transmit filters in the item. If all of an element’s
bound options are filtered out, then the element
is also filtered out. Use for no filtering.
included
Namespaces
String If set to null, a definition for each inherited
namespace is added to the root node of the
instance when it is extracted.
To filter the namespaces, list the prefixes for
those namespaces you want to include in the
instance, separated by spaces.
For example, to include only the xfdl and custom
namespaces, you would set this parameter to:
xfdl custom
Use #default to indicate the default namespace
for the instance.
Use an empty string (″″) to include only those
namespaces that are used by the instance.
Namespaces that are used in the instance are
always included, regardless of this setting.
theFile String The path to the file on the local drive that will
contain the XML instance.
theFlags Long Reserved. This must be 0.
theScheme String Reserved. Must be null.
theRootReference String A reference to the root node you want to extract.
This reference is relative to the instance node.
Use null to default to the instance node.
theNSNode IFormNodeP A node that inherits the namespaces used in the
reference. This node defines the namespaces for
the function. Use null if the node that this
function is operating on has inherited the
necessary namespaces.
Returns
Nothing if call is successful or throws a generic exception (UWIException) if an
error occurs.
Example
The following example shows a function that takes the root node of a form and
extracts an XML instance.
50
Sub SaveDataInstance(Form)
Form.ExtractInstance "Test", Nothing, vbNullString, _
"c:\InstanceData.txt", 0, vbNullString, vbNullString, Nothing
End Sub
ExtractXFormsInstance
Description
This function copies an XForms instance to a file or a memory block. This function
does not remove the instance from the form.
Call this function on the root node of the form or an instance node.
Note: This function automatically updates the XForms data model.
Function
Sub ExtractXformsInstance(
theModelID As String,
theNodeRef As String,
writeRelevant As Boolean,
IgnoreFailures As Boolean,
theNSNode As IFormNodeP,
theFilename As String,
theMemoryBlock As Variant)
Parameters
Expression Type Description
theModelID String The ID of the model to extract. Use
vbnullstring to extract the default model.
theNodeRef String An XPath reference to a node in the instance.
This node and all of its children are copied.
Leave blank to extract the entire instance.
writeRelevant Boolean If True, writes only relevant instance data.
ignoreFailures Boolean If True, ignores constraint or validation
failures.
theNSNode IFormNodeP A node that inherits the namespaces used in
the reference. This node defines the
namespaces for the function. Use nothing if
the node that this function is operating on
has inherited the necessary namespaces.
theFilename String The name and path of the file to write to.
Use vbnullstring to write to the output
memory block.
theMemoryBlock Variant The memory block that represents the
instance if you are not writing to a file.
Returns
Nothing if call is successful or throws an exception if an error occurs.
The FormNodeP Functions 51
Example
The following example shows a routine that takes the root node of a form, extracts
an XForms instance, and writes it to a file called ″InstanceData.xml″.
Sub SaveDataInstance(Form)
Form.ExtractXFormsInstance"model1",
"instance(’instance1’)loanrecord.user_personal_info", True, False,
Nothing, "c:\InstanceData.xml", Nothing
End Sub
GetAttribute
Description
This function returns the value of a specific attribute for a node. For example, the
following XFDL represents a MIME data node:
<mimedata encoding="base64"></mimedata>
In this sample, you could use GetAttribute to obtain the value of the encoding
attribute, which would be ″base64″.
Function
Function GetAttribute(
theNamespaceURI As String,
theAttribute As String
) As String
Parameters
Expression Type Description
theNamespaceURI String The namespace URI for the attribute. For
example:
http://www.ibm.com/xmlns/prod/XFDL/7.0
theAttribute String The local name of the attribute. For example,
encoding.
Returns
The attribute’s value or throws an exception if an error occurs. If the attribute is
empty or does not exist, the function returns null.
Notes
Namespaces
If you refer to an attribute with a namespace prefix, getAttribute first looks for a
complete match, including both prefix and attribute name. If it does not find such
a match, it will look for a matching attribute name that has no prefix but whose
containing element has the same namespace.
For example, assume that the custom namespace and the test namespace both
resolve to the same URI. In the following case, looking for the id attribute would
locate the second attribute (test:id), since it has an explicit namespace declaration:
52
<a xmlns:custom="ABC" xmlns:test="ABC">
<custom:myElement id="1" test:id="2">
</a>
However, in the next case, the id attribute does not have an explicit namespace
declaration. Instead, it inherits the custom namespace. However, since the inherited
namespace resolves to the same URI, the id attribute is still located:
<custom:myElement id="1">
Special Attributes
Forms generally use three special attributes that are not in an explicitly defined
namespace and which require special commands to retrieve.
The first is the default namespace attribute, which looks like this:
xmlns="http://www.ibm.com/xmlns/prod/XFDL/7.0"
To retrieve this attribute, you must use a namespace URI of null and the attribute
name xmlns.
The second special attribute is a namespace declaration, which looks like this:
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
To retrieve this sort of attribute, you must use the namespace URI
http://www.w3.org/2000/xmlns and the appropriate attribute name, such as custom.
Finally, there is the language attribute, which looks like this:
xml:lang="en-GB"
To retrieve this sort of attribute, you must use the namespace URI
http://www.w3.org/XML/1998/namespace and the attribute name lang.
Example
The following function uses DereferenceEx to locate a node that contains an
attachment. It then calls GetAttribute to retrieve the encoding type used, and
returns that value.
Function GetEncodingType(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Locate the mimedata option for the DATA1 node in PAGE3, which
’ contains an attachment.
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE3.DATA1.mimedata", 0, UFL_OPTION_REFERENCE, Nothing)
’ Get the encoding type of the data node.
GetEncodingType = TempNode.GetAttribute( _
"http://www.ibm.com/xmlns/prod/XFDL/7.0", "encoding")
End Function
The FormNodeP Functions 53
GetCertificateList
Description
This function locates all available certificates that can be used by a particular
signature button. The certificates are filtered according to the signature engine
defined in the signformat option of the button, and according to the filters defined
in the signdetails option of the button.
This function returns the valid certificates in an undetermined order. This means
that you cannot rely on the certificates being listed in the same order each time
you call this function.
Function
Function GetCertificateList(
theFilters As String,
theStatus As Long
) As CertificateList
Parameters
Expression Type Description
theFilters String A string that is used to filter the subject attribute
of the certificate. If the subject attribute include
this substring, then that certificate will be listed.
For example, you might filter against a name,
such as ″John Doe″, or an e-mail address, such as
″jdoe@ibm.com″.
Note that this filter is in addition to the other
filters defined in the signdetails option of the
button.
If null is passed, then only the filters in the
signdetails option are used.
theStatus Long This is a status flag that reports whether the
operation was successful. Possible values are:
SUSTATUS_OK — the operation was successful.
SUSTATUS_CANCELLED — the operation was
cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the
operation required user input, but could not
receive it (for example, it was run on a server
with no user).
Returns
An array containing the list of certificates objects.
Example
The following function uses DereferenceEx to locate a signature button in the
form. It then calls GetCertificateList to get a list of valid certificates for that
button. The function then loops through the available certificates, using
54
GetDataByPath to check the common name of each certicate. When it finds the
certificate with the common name of ″TJones″, it calls SignForm and uses that
certificate to sign the form.
Sub ApplySignature(Form)
Dim SigNode, SigObject ’ objects
Dim TheCerts ’ CertificateList
Dim CommonName ’ String
Dim Cert ’ ICertificate
’ Get the SignatureButton node
Set SigNode = Form.DereferenceEx(vbNullString, _
"PAGE1.SignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get available certificates for that button
Set TheCerts = SigNode.GetCertificateList(vbNullString, 1) ’vbNull
’ Test each of the available certificates to see if it has a common
’ name of "TJones". If it does, use that certificate to sign
’ the form.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "TJones" Then
Set SigObject = SigNode.SignForm(TheCerts(1), Nothing, 1)
’ vbNull
End If
Next
End Sub
GetChildren
Description
This function, along with GetParent, is used to traverse vertically along the form
hierarchy. GetChildren returns the first child of the indicated node. If the node has
no children, null is returned. All children of a particular IFormNodeP can be
traversed using an iterator, such as a while loop, in combination with GetNext.
Function
Function GetChildren() As IFormNodeP
Parameters
There are no parameters for this function.
Returns
The that represents the child or if no such child exists.
Example
getChildren returns the first child node of PAGE1.NAMELABEL that is
PAGE1.NAMELABEL.value.
The FormNodeP Functions 55
The following sample function receives any form node and returns a reference to
the last page of the form. First, the function uses GetNodeType to determine if the
supplied node is a the form level. If so, the function uses GetChildren to locate the
first page node. If not, the function uses GetParent to locate a page level node. The
function then uses GetNext to locate the last page in the form and calls
GetReferenceEx to retrieve a reference to that node.
Function GetLastPage(Node)
Dim MainNode, TestNode ’ objects
Set MainNode = Node
’ Locate the page level node that is the nearest ancestor or child of
’ the current node. If the node is a form node, get the child. If the
’ node is any other type, get the parent until a page node is
’ retrieved.
If MainNode.getNodeType = UFL_FORM Then
Set MainNode = MainNode.GetChildren
Else
’ Locate the page node of the form by iterating through the parents
’ of the supplied node. At the end of this loop, MainNode will be
’ a page node.
Do While (Not(MainNode.GetNodeType = UFL_PAGE))
Set MainNode = MainNode.GetParent
Loop
End If
’ Set TestNode to be the MainNode (the page node) before beginning the
’ next loop.
Set TestNode = MainNode
’ Locate the last page node by iterating through the siblings of the
’ global page node. At the end of this loop, TestNode will be Nothing
’ and MainNode will be the last page node.
Do While (Not(TestNode Is Nothing))
Set MainNode = TestNode
Set TestNode = TestNode.GetNext
Loop
’ Get a reference to the MainNode and return that reference to the
’ caller.
GetLastPage = MainNode.GetReferenceEx(vbNullString, Nothing, Nothing,_
False)
End Function
GetFormVersion
Description
This function determines the XFDL version of a form. You can call this function on
any form node that is in the XFDL namespace.
Function
Function GetFormVersion() As Integer
56
Parameters
There are no parameters for this function.
Returns
An integer in the form of &HMMmm0300, where MM is the major number and
mm is the minor number. For example, a version 6.3 form would return:
&H06030300.
Example
The following function accepts a form node and returns a boolean that indicates
whether the form is version 6.5 or higher.
Function CheckVersion(TheNode)
If (TheNode.GetFormVersion >= &H06050300) Then
CheckVersion = True
Else
CheckVersion = False
End If
End Function
GetIdentifier
Description
This function retrieves the identifier of a node. This is either the scope identifier or
option name for the node.
Function
Function GetIdentifier() As String
Parameters
There are no parameters for this function.
Returns
A string containing the identifier of the node or throws an exception if an error
occurs. If the identifier is empty or does not exist, the function returns null.
Example
The following function locates the first value option in a single page form, and
assumes that you pass it the root node of the form. First, the function uses
GetChildrenand GetNext to locate the first item in the first page. The function
then uses nested loops and GetNext to iterate through each option for each item in
the form, testing each option with GetIdentifier until it locates a value node.
Finally, the function returns the value node, or a null node if no value node was
found.
Function LocateFirstValue(Form)
Dim ItemNode, OptionNode ’ objects
Dim Found ’ Boolean
The FormNodeP Functions 57
Set ItemNode = Form
Found = False
’ Find the first item on the first page of the form. This takes three
’ separate calls, since we do not know the name of the first page or
’ item.
Set ItemNode = ItemNode.GetChildren
Set ItemNode = ItemNode.GetNext
Set ItemNode = ItemNode.GetChildren
’ Iterate through the items until one is found that contains a value
’ option or a null node is reached.
Do While (Not(ItemNode is Nothing))
’ Find the first option in the current item.
Set OptionNode = ItemNode.GetChildren
’ Iterate through the options until a "value" option is found or a
’ null node is reached.
Do While (Not(OptionNode is Nothing))
If OptionNode.GetIdentifier= "value" Then
Found = True
Exit Do
End If
Set OptionNode = OptionNode.GetNext
Loop
If Found Then Exit Do
Set ItemNode = ItemNode.GetNext
Loop
Set LocateFirstValue = OptionNode
End Function
GetLiteralByRefEx
Description
This function finds a particular IFormNodeP on the basis of a reference string. The
node you call this function on is used as the starting point for the search unless
you provide an absolute reference. Once the IFormNodeP is found, its literal is
retrieved.
Note: It is not necessary to call this function when you are using XForms. The
ReplaceXFormsInstance and ExtractXFormsInstancefunctions perform this
task automatically.
Function
Function GetLiteralByRefEx(
theScheme As String,
theReference As String,
theReferenceCode As Long,
theCharSet As String,
theNSNode As IFormNodeP
) As String
58
Parameters
Expression Type Description
theScheme String Reserved. This must be null.
theReference String The reference string.
theReferenceCode Long Reserved. This must be 0.
theCharSet String The character set you want to use to view the
literal string. Use null for ANSI/Unicode. Use
Symbol for Symbol.
theNSNode IFormNodeP A node that is used to resolve the namespaces
in theReference parameter (see the note about
namespace below). Use null if the node that this
function is operating on has inherited the
necessary namespaces.
Returns
The literal string or throws an exception if an error occurs. If the literal is empty or
does not exist, the function returns null.
Notes
IFormNodeP
Before you decide which IFormNodeP to call the function on, be sure you
understand the following:
1. The IFormNodeP supplied can never be more than one level in the hierarchy
above the starting point of the reference string. For example, if the reference
string begins with an option, then the IFormNodeP can be no higher in the
hierarchy than an item.
2. If the IFormNodeP is at the same level or lower in the hierarchy than the
starting point of the reference string, the function will attempt to locate a
common ancestor. The function will locate the ancestor of the IFormNodeP that
is one level in the hierarchy above the starting point of the reference string. The
function will then attempt to follow the reference string back down through the
hierarchy. If the reference string cannot be followed from the located ancestor
(for example, if the ancestor is not common to both the IFormNodeP and the
reference string), the function will fail.
For example, given a IFormNodeP that represents ″field_1″ and a reference of
″field_2″, the function will access the ″page″ node above ″field_1″, and will
then try to locate ″field_2″ below that node. If the two fields are not on the
same page, the function will fail.
3. If the IFormNodeP is at the argument level, the search will not start from that
point. Instead, the nearest ancestor that is at the option level will be used as the
starting point for the search.
Creating a Reference String
For more information about creating a reference, see “References” on page 6.
Determining Namespace
The FormNodeP Functions 59
In some cases, you may want to use the GetLiteralByRefEx function to get the
literal of a node that does not have a globally defined namespace. For example,
consider the following form:
<label sid="Label1">
<value>Field1.processing:myValue</value>
</label>
<field sid="Field1" xmlns:processing="URI">
<value></value>
<processing:myValue>10<processing:myValue>
</field>
In this form, the processing namespace is declared in the Field1 node. Any elements
within Field1 will understand that namespace; however, elements outside of the
scope of Field1 will not.
In cases like this, you will often start your search at a node that does not
understand the namespace of the node you are trying to locate. For example, you
might want to locate the node referenced in the value of Label1. In this case, you
would first locate the Label1 value node and get its literal. Then, from the Label1
value node, you would attempt to locate the processing:myValue node as shown:
Label1Node.GetLiteralByRefEx(vbNullString, "Field1.processing:myValue",
0, vbNullString, vbNullString)
In this example, the GetLiteralByRefEx function would fail. The function cannot
properly resolve the processing namespace because this namespace is not defined
for the Label1 value node. To correct this, you must also provide a node that
understands the processing namespace (in this case, any node in the scope of Field1)
as a parameter in the function:
Label1Node.GetLiteralByRefEx(vbNullString, "Field1.processing:myValue",
0, vbNullString, Field1Node)
Example
The following example adds a label to a form. A node is passed into the function,
which then uses GetLiteralByRefEx to read the value of a field. The function then
uses DereferenceEx to locate the field node, and creates a label node as a sibling
using Create. Finally, the function creates a value for the new label node using
SetLiteralByRef.
Sub AddLabel(Form)
Dim TempNode, XFDL ’ objects
Dim Name ’ strings
Set TempNode = Form
’ Get the value of the NameField.value option node
Name = TempNode.GetLiteralByRefEx(vbNullString, _
"PAGE1.NameField.value", 0, vbNullString, Nothing)
’ Locate the NameField item node in the first page of the form
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameField", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get an XFDL object
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Create a label. This label is created as a sibling of the NameField,
’ and is named NameLabel.
60
Set TempNode = XFDL.Create(TempNode, UFL_AFTER_SIBLING, "label", _
vbNullString, vbNullString, "NameLabel")
’ Create a value option for the label. This option is assigned the
’ value of Name (as read from the field)
TempNode.SetLiteralByRefEx vbNullString, "value", 0, vbNullString, _
Nothing, Name
End Sub
GetLiteralEx
Description
This function retrieves the literal of a node. The literal is returned in the specified
character set.
Note: It is not necessary to call this function when you are using XForms. The
ReplaceXFormsInstance and ExtractXFormsInstancefunctions perform this
task automatically.
Function
Function GetLiteralEx(
theCharSet As String
) As String
Parameters
Expression Type Description
theCharSet String The character set you want to use to view the
literal string. . Use null for ANSI/Unicode. Use
Symbol for Symbol.
Returns
A string containing the literal of the node or throws an exception if an error
occurs. If the literal is empty or does not exist, the function returns null.
Example
The following function copies the value from one field to another. First, the
function uses DeferenceEx to locate the value node of a field on page one and
reads the value using GetLiteral. Next, teh function locates a value node on page
two and writes the literal to that field using SetLiteral.
Sub CopyValue(Form)
Dim TempNode ’ object
Dim theName ’ string
Set TempNode = Form
’ Locate the NameField on page 1
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameField.value", 0, UFL_OPTION_REFERENCE, Nothing)
’ Get the literal from the value node
The FormNodeP Functions 61
theName = TempNode.GetLiteralEx
’ Locate the NameField on page 2
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE2.NameField.value", 0, UFL_OPTION_REFERENCE, Nothing)
’ Write the literal that was read from the first value node
TempNode.SetLiteral theName
End Sub
GetLocalName
Description
This function returns the local name of a given node. The local name is determined
by the XML tag that represents that node. For example, examine the following
XML fragment:
<page sid="PAGE1">
<global sid="global"></global>
<field sid="testField">
<value>Hello</value>
<bgcolor>
<ae>120</ae>
<ae>120</ae>
<ae>120</ae>
<bgcolor>
</field>
</page>
In this sample, the name of the page node is ″page″, the name of the field node is
″field″, the name of the value node is ″value″, and the name of the bgcolor node is
″bgcolor″. The bgcolor node is also the parent of three array element nodes, all of
which are named ″ae″.
Note that the local name does not include any namespace prefix that might exist.
For example, you might have a custom option in a different namespace as shown:
<field sid="testField">
<custom:my_option>value</custom:my_option>
</field>
In this case, the local name of the custom option is returned without the prefix,
resulting in ″my_option″.
Function
Function GetLocalName() As String
Parameters
There are no parameters for this function.
Returns
The name of the node or throws an exception if an error occurs.
62
Example
The following function uses GetChildren and GetNext to walk through the entire
form recursively. While walking through the form, the function uses IsXFDL and
GetLocalName to test each node in the form and determine whether it is an XFDL
label node. If so, the function uses SetLiteralByRefEx to set the label’s background
color to green.
Sub ChangeLabelColor(Node)
Dim TempNode, BGColorNode ’ objects
’ Use recursion to step through each node in the form
Set TempNode = Node.GetChildren
Do While (Not(TempNode Is Nothing))
ChangeLabelColor(TempNode)
Set TempNode = TempNode.GetNext
Loop
’ If the node is a label in the XFDL namespace, locate the background
’ color child node and change its value to green.
If ((Node.IsXFDL) And (Node.GetLocalName = "label")) Then
Node.SetLiteralByRefEx vbNullString, "bgcolor[0]", 0, _
vbNullString, Nothing, "green"
End If
End Sub
GetNamespaceURI
Description
This function returns the namespace URI for the node.
Each namespace is defined in the form by a namespace declaration, as shown:
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
Each namespace declaration defines both a prefix and a URI for the namespace. In
this sample, the prefix for the XFDL namespace is xfdl and the URI is
http://www.ibm.com/xmlns/prod/XFDL/7.0.
Tags within the form are assigned specific namespaces by using the defined prefix.
For example, to declare that an option was in the custom namespace you would
use the prefix custom as shown:
<field sid="testField">
<custom:custom_option>value</custom:custom_option>
</field>
Function
Function GetNamespaceURI() As String
Parameters
There are no parameters for this function.
The FormNodeP Functions 63
Returns
The namespace URI or throws an exception if an error occurs.
Example
The following function uses GetChildren and GetNext to walk through an entire
form. While walking through the form, it uses GetNamespaceURI to determine
whether each node is in the Custom namespace identified by the following URI:
http://www.ibm.com/xmlns/prod/XFDL/Custom. If so, the function destroys the node.
This function assumes that you are passing the root node of the form on the first
call. Subsequent calls occur through recursion, which may provide any level of
node.
Sub DeleteCustomNamespace(Node)
Dim MainNode, TestNode ’ objects
Dim TempInt
’ Set the MainNode to be the child of the provided node.
Set MainNode = Node.GetChildren
’ Use recursion to step through each node in the form. This routine
’ walks to the last node in each page, then traverses back up the tree,
’ deleting nodes that are not in the XFDL namespace as it goes.
Do While (Not(MainNode Is Nothing))
Set TestNode = MainNode.GetNext
DeleteCustomInfo(MainNode)
Set MainNode = TestNode
Loop
’ Check to see if the node passed to the routine is in the Custom
’ namespace. If so, delete the node.
If Node.GetNamespaceURI = "http://www.ibm.com/xmlns/prod/XFDL/Custom" Then
Node.Destroy
End If
End Sub
GetNamespaceURIFromPrefix
Description
This function returns the namespace URI that corresponds to a specific prefix. You
can call this function from any node in the form, as long as that node either
declares or inherits the namespace in question.
Each namespace is defined in the form by a namespace declaration, as shown:
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
Each namespace declaration defines both a prefix and a URI for the namespace. In
this sample, the prefix for the XFDL namespace is xfdl and the URI is
http://www.ibm.com/xmlns/prod/XFDL/7.0.
Tags within the form are assigned specific namespaces by using the defined prefix.
For example, to declare that an option was in the custom namespace you would
use the prefix custom as shown:
64
<field sid="testField">
<custom:custom_option>value</custom:custom_option>
</field>
Function
Function GetNamespaceURIFromPrefix(
thePrefix As String
) As String
Parameters
Expression Type Description
thePrefix String The namespace prefix. For example, xfdl.
Returns
The namespace URI or throws an exception if an error occurs. If the namespace
URI is not declared, the result is null.
Example
The following function copies an option in the custom namespace from one form
to another. First, it uses GetNamespaceURIFromPrefix to get the URI for the
custom namespace from Form1, then uses AddNamespace to add that namespace
to Form2. Next, it uses DereferenceEx to locate the custom node in Form1 and the
global page’s global item in Form2. Finally, it uses Duplicate to copy the custom
node from Form1 into Form2, creating it as a child of the global item.
Sub CopyCustomInfo(Form1, Form2)
Dim TheURI ’ String
Dim TempNode, DuplicateNode, GlobalNode ’ IFormNodeP
’ Get the URI for the custom namespace in Form1.
TheURI = Form1.GetNamespaceURIFromPrefix("custom")
’ Create the custom namespace in Form2 using the URI from Form1.
Form2.AddNamespace TheURI, "custom"
’ Locate the custom processing node in Form1.
Set TempNode = Form1.DereferenceEx(vbNullString, _
"global.global.custom:processing", 0, UFL_OPTION_REFERENCE, _
Nothing)
’ Locate the global item in Form2
Set GlobalNode = Form2.DereferenceEx(vbNullString, "global.global", _
0, UFL_ITEM_REFERENCE, Nothing)
’ Copy the custom node from Form1 and insert it as the child of the
’ global item in Form2.
Set DuplicateNode = TempNode.duplicate(GlobalNode, _
UFL_APPEND_CHILD, vbNullString)
End Sub
The FormNodeP Functions 65
GetNext
Description
This function, along with GetPrevious, is used to traverse horizontally along the
form hierarchy. GetNext returns the next node in the tree. For instance, the page
node corresponding to the first page of your form can be reached by calling
GetNext on the global page node.
Function
Function GetNext() As IFormNodeP
Parameters
There are no parameters for this function.
Returns
The IFormNodeP that represents the next node or null if no such node exists.An
exception is thrown if an error occurs.
Example
The following sample function receives any form node and returns a reference to
the last page of the form. First, the function uses GetNodeType to determine if the
supplied node is a the form level. If so, the function uses GetChildren to locate the
first page node. If not, the function uses GetParent to locate a page level node. The
function then uses GetNext to locate the last page in the form and calls
GetReferenceEx to retrieve a reference to that node.
Function GetLastPage(Node)
Dim MainNode, TestNode ’ objects
Set MainNode = Node
’ Locate the page level node that is the nearest ancestor or child of
’ the current node. If the node is a form node, get the child. If the
’ node is any other type, get the parent until a page node is
’ retrieved.
If MainNode.getNodeType = UFL_FORM Then
Set MainNode = MainNode.GetChildren
Else
’ Locate the page node of the form by iterating through the parents
’ of the supplied node. At the end of this loop, MainNode will be
’ a page node.
Do While (Not(MainNode.GetNodeType = UFL_PAGE))
Set MainNode = MainNode.GetParent
Loop
End If
’ Set TestNode to be the MainNode (the page node) before beginning the
’ next loop.
Set TestNode = MainNode
’ Locate the last page node by iterating through the siblings of the
’ global page node. At the end of this loop, TestNode will be Nothing
’ and MainNode will be the last page node.
66
Do While (Not(TestNode Is Nothing))
Set MainNode = TestNode
Set TestNode = TestNode.GetNext
Loop
’ Get a reference to the MainNode and return that reference to the
’ caller.
GetLastPage = MainNode.GetReferenceEx(vbNullString, Nothing, Nothing,_
False)
End Function
GetNodeType
Description
This function returns the type for a node (for example, page, item, option, and so
on). This allows you to quickly determine the type of node you are working with
and what depth you are at in the node hierarchy.
Function
Function GetNodeType() As Long
Parameters
There are no parameters for this function.
Returns
This method throws a generic exception (UWIException) if an error occurs.
One of the following types:
v UFL_FORM — The root node of the form.
v UFL_PAGE — A page level node.
v UFL_ITEM — An item level node.
v UFL_OPTION — An option level node.
v UFL_ARRAY — An argument level node, such as an array element.
This function throws an exception if an error occurs.
Example
The following function recieves a node below the page level and uses GetParent to
ascend the hierarchy until it reaches a page node, as detected by GetNodeType.
The following sample function receives any form node and returns a reference to
the last page of the form. First, the function uses GetNodeType to determine if the
supplied node is a the form level. If so, the function uses GetChildren to locate the
first page node. If not, the function uses GetParent to locate a page level node. The
function then uses GetNext to locate the last page in the form and calls
GetReferenceEx to retrieve a reference to that node.
Function GetLastPage(Node)
Dim MainNode, TestNode ’ objects
Set MainNode = Node
The FormNodeP Functions 67
’ Locate the page level node that is the nearest ancestor or child of
’ the current node. If the node is a form node, get the child. If the
’ node is any other type, get the parent until a page node is
’ retrieved.
If MainNode.getNodeType = UFL_FORM Then
Set MainNode = MainNode.GetChildren
Else
’ Locate the page node of the form by iterating through the parents
’ of the supplied node. At the end of this loop, MainNode will be
’ a page node.
Do While (Not(MainNode.GetNodeType = UFL_PAGE))
Set MainNode = MainNode.GetParent
Loop
End If
’ Set TestNode to be the MainNode (the page node) before beginning the
’ next loop.
Set TestNode = MainNode
’ Locate the last page node by iterating through the siblings of the
’ global page node. At the end of this loop, TestNode will be Nothing
’ and MainNode will be the last page node.
Do While (Not(TestNode Is Nothing))
Set MainNode = TestNode
Set TestNode = TestNode.GetNext
Loop
’ Get a reference to the MainNode and return that reference to the
’ caller.
GetLastPage = MainNode.GetReferenceEx(vbNullString, Nothing, Nothing,_
False)
End Function
GetParent
Description
This function, along with GetChildren, is used to traverse vertically along the
form hierarchy. GetParent returns the parent of a node. If the node has no parent,
null is returned. A form’s structure can be traversed up to the root node using an
iterator such as a while loop.
Function
Function GetParent() As IFormNodeP
Parameters
There are no parameters for this function.
Returns
The IFormNodeP that represents the parent node or null if no such parent exists. If
an error occurs, an exception is thrown.
68
Example
getParent returns the parent node of PAGE1.AGEFIELD.size, that is,
PAGE1.AGEFIELD.
The following sample function receives any form node and returns a reference to
the last page of the form. First, the function uses GetNodeType to determine if the
supplied node is a the form level. If so, the function uses GetChildren to locate the
first page node. If not, the function uses GetParent to locate a page level node. The
function then uses GetNext to locate the last page in the form and calls
GetReferenceEx to retrieve a reference to that node.
Function GetLastPage(Node)
Dim MainNode, TestNode ’ objects
Set MainNode = Node
’ Locate the page level node that is the nearest ancestor or child of
’ the current node. If the node is a form node, get the child. If the
’ node is any other type, get the parent until a page node is
’ retrieved.
If MainNode.GetNodeType = UFL_FORM Then
Set MainNode = MainNode.GetChildren
Else
’ Locate the page node of the form by iterating through the parents
’ of the supplied node. At the end of this loop, MainNode will be
’ a page node.
Do While (Not(MainNode.GetNodeType = UFL_PAGE))
Set MainNode = MainNode.GetParent
Loop
End If
’ Set TestNode to be the MainNode (the page node) before beginning the
’ next loop.
Set TestNode = MainNode
’ Locate the last page node by iterating through the siblings of the
’ global page node. At the end of this loop, TestNode will be Nothing
’ and MainNode will be the last page node.
Do While (Not(TestNode Is Nothing))
Set MainNode = TestNode
Set TestNode = TestNode.GetNext
Loop
’ Get a reference to the MainNode and return that reference to the
’ caller.
GetLastPage = MainNode.GetReferenceEx(vbNullString, Nothing, Nothing,_
False)
End Function
GetPrefix
Description
This function returns the namespace prefix for the node.
Each namespace is defined in the form by a namespace declaration, as shown:
The FormNodeP Functions 69
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
Each namespace declaration defines both a prefix and a URI for the namespace. In
this sample, the prefix for the XFDL namespace is xfdl and the URI is
http://www.ibm.com/xmlns/prod/XFDL/7.0.
Tags within the form are assigned specific namespaces by using the defined prefix.
For example, to declare that an option was in the custom namespace you would
use the prefix custom as shown:
<field sid="testField">
<custom:custom_option>value</custom:custom_option>
</field>
Note: A given prefix may not always resolve to the same namespace. Different
portions of the form may define the prefix differently. For example, the
custom prefix may resolve to a different namespace on the first page of a
form than it does on the following pages.
Function
Function GetPrefix() As String
Parameters
There are no parameters for this function.
Returns
The prefix for the node’s namespace or throws an exception if an error occurs.
Example
The following function removes all nodes from the form that have a namespace
prefix of ″custom″. The function walks through the form using GetChildren and
GetNext in a recursive loop. While walking the form, it uses GetPrefix to locate
nodes in the custom namespace and deletes them using Destroy. This function
assumes that you are passing it the root node of the form.
Sub DeleteCustomPrefix(Node)
Dim TempNode, TempNode2 ’ IFormNodeP
’ Use recursion to step through each node of the form.
Set TempNode = Node.GetChildren
Do While (Not(TempNode is Nothing))
Set TempNode2 = TempNode.GetNext
DeleteCustomPrefix(TempNode)
Set TempNode = TempNode2
Loop
’ If the node has a namespace prefix of "custom", delete it.
If (Node.GetPrefix = "custom") Then
Node.Destroy
End If
End Sub
70
GetPrefixFromNamespaceURI
Description
This function returns the namespace prefix for a specific namespace URIYou can
call this function from any node in the form, as long as that node either declares or
inherits the namespace in question.
Each namespace is defined in the form by a namespace declaration, as shown:
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
Each namespace declaration defines both a prefix and a URI for the namespace. In
this sample, the prefix for the XFDL namespace is xfdl and the URI is
http://www.ibm.com/xmlns/prod/XFDL/7.0.
Tags within the form are assigned specific namespaces by using the defined prefix.
For example, to declare that an option was in the custom namespace you would
use the prefix custom as shown:
<field sid="testField">
<custom:custom_option>value</custom:custom_option>
</field>
Function
Function GetPrefixFromNamespaceURI(
theURI As String
) As String
Parameters
Expression Type Description
theURI String The namespace URI. For example:
http://www.ibm.com/xmlns/prod/XFDL/7.0
Returns
The namespace prefix or throws an exception if an error occurs. If the namespace
URI is not declared, the result is null.
Example
The following function adds some custom user information to the form, but
assumes that the prefix used for the custom namespace is unknown. The function
first uses GetPrefixFromNamespaceURI to determine which prefix is used for the
custom namespace. It then concatenates that prefix with the tag ″:User″ to create
the name for a new node. Next, it uses DereferenceEx to locate the global item in
the global page. Finally, it uses Create to add a custom option called ″User″ to the
form.
Sub AddUserInfo(Form, UserName)
Dim XFDL, TempNode ’ objects
Dim ThePrefix, NewName ’ Strings
Set TempNode = Form
’ Retrieve the prefix for the custom namespace
The FormNodeP Functions 71
ThePrefix = TempNode.GetPrefixFromNamespaceURI( _
"http://www.ibm.com/xmlns/prod/XFDL/Custom")
’ Create a name for a new node by concatenating the prefix with ":User"
NewName = ThePrefix & ":User"
’ Locate the global item in the global page so we can add a global
’ option
Set TempNode = TempNode.DereferenceEx(vbNullString, "global.global", _
0, UFL_ITEM_REFERENCE, Nothing)
’ Create an XFDL object so we can use the create function
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Create new node in the custom namespace that represents the user of
’ the form and give it a value of "TJones"
Set TempNode = XFDL.Create(TempNode, UFL_APPEND_CHILD, vbNullString, _
UserName , vbNullString, NewName)
End Sub
GetPrevious
Description
This function, along with GetNext, is used to traverse horizontally along the form
hierarchy. GetPrevious returns the previous node in the tree. For instance, if you
call GetPrevious one the Page1 node in your form, it will return the global page
node.
Function
Function GetPrevious() As IFormNodeP
Parameters
There are no parameters for this function.
Returns
The IFormNodeP that represents the previous node or null if no such node exists.
An exception is thrown if an error occurs.
Example
The following sample function receives any form node and returns a reference to
the first page of the form. First, the function uses GetNodeType to determine if the
supplied node is a the form level. If so, the function uses GetChildren to locate the
first page node. If not, the function uses GetParent to locate a page level node. The
function then uses GetPrevious to locate the first page in the form and calls
GetReferenceEx to retrieve a reference to that node.
Function GetFirstPage(Node)
Dim MainNode, TestNode ’objects
Set MainNode = Node
’ Locate the page level node that is the nearest ancestor or child of
72
’ the current node. If the node is a form node, get the child. If the
’ node is any other type, get the parent until a page node is
’ retrieved.
If MainNode.GetNodeType = UFL_FORM Then
Set MainNode = MainNode.GetChildren
Else
’ Locate the page node of the form by iterating through the parents
’ of the supplied node. At the end of this loop, MainNode will be
’ the page node.
Do While (Not(MainNode.GetNodeType = UFL_PAGE))
Set MainNode = MainNode.GetParent
Loop
End If
’ Set TestNode to be the MainNode before beginning the next loop
Set TestNode = MainNode
’ Locate the first page node (the global page) by iterating through the
’ siblings of the located page node. At the end of this loop, TestNode
’ will be Nothing and MainNode will be the global page node.
Do While (Not(TestNode Is Nothing))
Set MainNode = TestNode
Set TestNode = TestNode.GetPrevious
Loop
’ Locate the first page of the form by getting the first sibling of the
’ global page node.
Set MainNode = MainNode.GetNext
’ Get a reference to the page and return the reference to the caller
GetFirstPage = MainNode.GetReferenceEx(vbNullString, Nothing, _
Nothing, False)
End Function
GetReferenceEx
Description
This function returns the reference string that identifies the node. For example, a
value node might return a reference of Page1.Field1.value. The reference will either
begin at the page level of the form or at a level specified by the caller.
Function
Function GetReferenceEx(
theScheme As String,
theNSNode As IFormNodeP,
theStartPoint As IFormNodeP,
addNamespaces As Boolean
) As String
Parameters
Expression Type Description
theScheme String Reserved. This must be null.
The FormNodeP Functions 73
Expression Type Description
theNSNode IFormNodeP A node that defines which namespace prefixes are
used when constructing the reference. Only
namespace prefixes that this node inherits are used.
Use null if the node that this function is operating on
has inherited the necessary namespaces.
theStartPoint IFormNodeP A node that determines the starting point of the
reference. This node must be a parent of the aNode
parameter. The reference will begin one level below
the start point node. For example, if you provide a
page node the reference will begin at the item level.
Use null to start the reference at the page level.
addNamespaces Boolean Use True to add declarations for unknown
namespaces to the namespace node (theNSNode).
Otherwise, use False.
Returns
A string containing a reference to the node, or throws an exception if an error
occurs.
Notes
Creating a Reference String
For more information about creating a reference, see “References” on page 6.
Working with Namespace Prefixes
In some cases, you may want to use the GetReferenceEx function to get the
reference to a node that uses a different prefix for a known namespace. For
example, consider the following form:
<label sid="Label1" xmlns:data="URI">
<value></value>
</label>
<field sid="Field1" xmlns:processing="URI">
<value></value>
<processing:myValue>10<processing:myValue>
</field>
In this form, processing and data are prefixes for the same namespace, since they
both refer to the same URI. However, both namespaces have limited scope since
they are declared at the item level. This means that Label1 node does not
understand the processing prefix, and that the Field1 node does not understand the
data prefix.
This becomes a problem if you want to refer to a namespace from a location that
does not understand that namespace. For example, suppose you wanted to set the
value of Label1 to be a reference to the myValue node in Field1. Normally, you
would locate the myValue node and use getReferenceEx as shown:
myValueNode.GetReferenceEx(vbNullString, Nothing, Nothing, False)
In this case, GetReferenceEx would return the following reference:
Page1.Field1.processing:myValue. However, because the processing namespace is not
74
defined for Label1, a reference to the processing namespace is not understood. This
means that you cannot set the value of Label1 to equal this reference, since the
node would not understand that content.
Instead, you must generate a reference that includes a known namespace prefix,
such as the data namespace. You can do this by including a second node in the
GetReferenceEx function. The second node must understand the appropriate
namespace. For example, you could include the Label1 node in the function, as
shown:
myValueNode.GetReferenceEx(vbNullString, Label1Node, Nothing, False)
In this case, the function will substitute the data prefix for the processing prefix,
since they both resolve to the same namespace. As a result, the function will
return: Page1.Field1.data:myValue. Since the data prefix is defined within Label1, you
can use this reference to set Label1’s value node.
Working with Unknown Namespaces
In some cases, you may want to use the GetReferenceEx function to get the
reference to a node that uses an unknown namespace. For example, consider the
following form:
<page sid="Page1" xmlns:processing="URI1">
<global sid="global">
<processing:info></processing:info>
</global>
<field sid="Field1" xmlns:data="URI2">
<value></value>
<data:info>data</data:info>
</field>
In this example, you might want to store a reference to the <data:info> element in
the <processing:info> element. GetReferenceEx would return the following
reference for the <data:info> element: Page1.Field1.data:info. However, this reference
includes the data namespace, which is not defined for the page global. This means
that you could not store this reference in the <processing:info> element, because it
would not understand the reference.
To solve this problem, you can use the addNamespaces flag in the GetReferenceEx
function. When this flag is set to True, the function will add unknown namespaces
to the theNSNode.
For example, if you set theNSNode to be the global item node for Page1, and set the
addNamespace flag to True, as shown:
dataNode.GetReferenceEx(vbNullString, pageGlobalNode, Nothing, True)
The function would return the reference to the <data:info> element, but would also
modify the global item node to include the unknown data namespaces, as shown:
<global sid="global" xmlns:data="URI2">
You could then store the reference in that global item or any of its descendants,
since the namespace is now properly defined.
The FormNodeP Functions 75
Example
In the following example, a page node is passed to the . The then uses and to
locate the last item node in the page. is then called to get the reference to that
node, which is returned to the caller.
The following sample function receives any form node and returns a reference to
the last page of the form. First, the function uses GetNodeType to determine if the
supplied node is a the form level. If so, the function uses GetChildren to locate the
first page node. If not, the function uses GetParent to locate a page level node. The
function then uses GetNext to locate the last page in the form and calls
GetReferenceEx to retrieve a reference to that node.
Function GetLastPage(Node)
Dim MainNode, TestNode ’ objects
Set MainNode = Node
’ Locate the page level node that is the nearest ancestor or child of
’ the current node. If the node is a form node, get the child. If the
’ node is any other type, get the parent until a page node is
’ retrieved.
If MainNode.getNodeType = UFL_FORM Then
Set MainNode = MainNode.GetChildren
Else
’ Locate the page node of the form by iterating through the parents
’ of the supplied node. At the end of this loop, MainNode will be
’ a page node.
Do While (Not(MainNode.GetNodeType = UFL_PAGE))
Set MainNode = MainNode.GetParent
Loop
End If
’ Set TestNode to be the MainNode (the page node) before beginning the
’ next loop.
Set TestNode = MainNode
’ Locate the last page node by iterating through the siblings of the
’ global page node. At the end of this loop, TestNode will be Nothing
’ and MainNode will be the last page node.
Do While (Not(TestNode Is Nothing))
Set MainNode = TestNode
Set TestNode = TestNode.GetNext
Loop
’ Get a reference to the MainNode and return that reference to the
’ caller.
GetLastPage = MainNode.GetReferenceEx(vbNullString, Nothing, Nothing,_
False)
End Function
76
GetSecurityEngineName
Description
This function returns the name of the appropriate security engine for a given
button or signature node. This is useful for determining which validation call you
need to make to validate the signature.
Function
Function GetSecurityEngineName(
theOperation As Long
) As String
Parameters
Expression Type Description
theOperation Long The operation you want the security engine for.
Possible values are:
SEOPERATION_SIGN — the engine is needed to sign
the form.
SEOPERATION_VERIFY — the engine is needed to
verify the signature.
SEOPERATION_LISTIDENTITIES — the engine is
needed to generate a list of valid certificates for
signing.
Returns
A string containing the name of the security engine on success, or throws an
exception if an error occurs. The possible names are:
v CryptoAPI
v Netscape
v ClickWrap
v HMAC-ClickWrap
v PenOp
Example
The following function uses GetSecurityEngineName to determine which engine
to use to verify the signature. It then calls the appropriate verification function.
Note that the verification functions are not themselves API functions, but would
use functions within the API such as VerifySignature and
ValidateHMACWithSecret.
Function CheckSignatureByType(SigNode)
Dim EngineName, Status ’ String
’ Get the name of the signature engine that can verify the signature
EngineName = SigNode.GetSecurityEngineName(SEOPERATION_VERIFY)
’ If the signature engine is HMAC, call ValidateHMACSig, otherwise call
’ CheckSignature.
The FormNodeP Functions 77
If EngineName = "HMAC-ClickWrap" Then
Status = ValidateHMACSig(SigNode)
Else
Status = CheckSignature(SigNode)
End If
’ Return the signature status
CheckSignatureByType = Status
End Function
GetSigLockCount
Description
This function returns the signature lock count of a node. If 0 is returned, the node
is not signed by any digital signature, but it may have descendants that are signed.
Function
Function GetSigLockCount() As Integer
Parameters
There are no parameters for this function.
Returns
The number of locks on the the given node or throws an exception if an error
occurs.
Example
The following function uses GetSigLockCount to determine whether a node has
been signed. If so, the function returns True; otherwise, the function returns False.
Function CheckSigned(Node)
’ Check to see if the node has a any signature locks. If so, return
’ True to show that is signed; otherwise, return false.
If Node.GetSigLockCount > 0 Then
CheckSigned = True
Else
CheckSigned = False
End If
End Function
GetSignature
Description
This function returns signature object for a given button or signature item.
Function
Function GetSignature() As ISignature
78
Parameters
There are no parameters for this function.
Returns
A signature object if the call is successful, or throws an exception if an error occurs.
Example
The following function uses DereferenceEx and GetLiteralByRefEx to locate the
signature item in a form. It then uses GetEngineCertificateList and
GetDataByPath to locate a server signing certificate. Next, it uses GetSignature
and GetDataByPath to get the signer’s common name. Finally, it uses
ValidateHMACWithSecret to determine if the HMAC signature is valid, and
returns ″Valid″ or ″Invalid″, as appropriate.
Function ValidateHMACSig(Form)
Dim SigObject, XFDL ’ Objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, CommonName, SigItemRef ’ Strings
Dim Validation ’ Integer
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
The FormNodeP Functions 79
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret,
’ and sets SharedSecret to match. In most cases, this would be a
’ database lookup. For the purposes of this example, we will simply
’ assign a value to SharedSecret.
SharedSecret = "secret"
’ Validate the signature
Validation = SigNode.ValidateHMACWithSecret(SharedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSig = "Valid"
Else
ValidateHMACSig = "Invalid"
End If
End Function
GetSignatureVerificationStatus
Description
When called, this function checks to see if the digital signatures in a given form
are valid.
Function
Function GetSignatureVerificationStatus() As Integer
Parameters
There are no parameters for this function.
Returns
An Integer having one of the following values:
Code Status
UFL_SIGS_OK The signatures are valid.
UFL_SIGS_NOTOK One or more signatures are broken.
UFL_SIGS_UNVERIFIED One or more signatures are unverifiable.
On error, the function throws an exception.
Example
The following function checks to see if all of the signatures in the form are valid
by calling GetSignatureVerificationStatus. This relies on a flag that was set when
80
the form was first read, and does not return the current status of the signatures. If
the signatures were valid when the form was read, the function returns ″Valid″;
otherwise, the functions returns ″Invalid″.
Function CheckSignatures(Form)
Dim TempNode ’ objects
Dim SigStatus ’ Integer
Set TempNode = Form
’ Check to see if the signatures were valid when the form was read.
SigStatus = TempNode.GetSignatureVerificationStatus
’ If the signatures are not valid, then return "Invalid". If the
’ signatures are valid, then return "Valid".
If (Not(SigStatus = 0)) Then ’ 0 = UFL_SIGS_OK
CheckSignatures = "Invalid"
Else
CheckSignatures = "Valid"
End If
End Function
GetType
Description
This function retrieves the type of a node. Possible types include global, page, and
all item names (such as action, button, and so on).
Function
Function GetType() As String
Parameters
There are no parameters for this function.
Returns
A string containing the type of the node or throws an exception if an error occurs.
If the type is empty or does not exist, the function returns null.
Example
The following function locates the first field in a single page form. First, the
function uses GetChildren and GetNext to locate the first item in the first page.
The function then uses GetNext to iterate through each item in the page, testing
each item with GetType to determine whether it is a field. Finally, the function
returns the field node, or a null node if no field is found.
Function LocateFirstField(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Find the first item on the first page of the form.
Set TempNode = TempNode.GetChildren
The FormNodeP Functions 81
Set TempNode = TempNode.GetNext
Set TempNode = TempNode.GetChildren
’ Iterate through the items until the first field is located or an
’ empty node is returned.
Do While (Not(TempNode.GetType = "field")) And (Not(TempNode is _
Nothing))
Set TempNode = TempNode.GetNext
Loop
’ Return the node. If no field node is found, a null node is returned.
Set LocateFirstField = TempNode
End Function
IsSigned
Description
This function determines whether a node is signed.
Function
Function IsSigned(
excludeSelf As Boolean
) As Boolean
Parameters
Expression Type Description
excludeSelf Boolean A signature node is always self-signed. To
determine whether a second signature has been
applied to that node, you must exclude the
self-signing from this check.
To exclude the self-signing from the signature
check, set this to True. To include the
self-signing, set this to False.
Returns
True if the node is signed, False if it is not.
Example
The following function locates the value node for a Date field, checks to see if it is
signed, and sets the value if the node is not signed.
Sub SetDateValue(theDate, TheForm)
Dim TempNode ’ object
’ Locate the value option for the Date field
Set TempNode = TheForm.DereferenceEx(vbNullString, _
"PAGE1.Date.value", 0, UFL_OPTION_REFERENCE, Nothing)
’ Check the value node to see if it is signed. If it is not signed,
’ set it to the value passed into the function.
82
If TempNode.IsSigned(False) = False Then
TempNode.SetLiteralEx vbNullString, theDate
End If
End Sub
IsValidFormat
Description
This function returns the boolean result of whether a string is valid according to
the setting of the node’s format option.
This function does not support XForms nodes.
Function
Function IsValidFormat(
theString As String
) As Boolean
Parameters
Expression Type Description
theString String A string to be checked against the format. For
example, to check 23.2 against a specific format,
the string would be “23.2”.
Returns
True if the string does match the format, False if it does not.
Example
The following function locates the Currency field and checks to see if “23.2”
conforms to the format required by the field’s format option.
Sub CheckFormat(TheForm)
Dim theItem ’ object
’ Locate the Currency field
Set theItem = TheForm.DereferenceEx(vbNullString, _
"PAGE1.Currency", 0, UFL_OPTION_REFERENCE, Nothing)
’ Check the string to see if it is valid. If it is valid, then
’ enter the string into the Currency field.
’ Otherwise, do nothing.
If theItem.IsValidFormat("23.2") = True Then
theItem.SetLiteralByRefEx vbNullString, "value", 0, vbNullString, Nothing, _
"23.2"
End If
End Sub
The FormNodeP Functions 83
IsXFDL
Description
This function determines whether a node belongs to the XFDL namespace.
Each namespace is defined in the form by a namespace declaration, as shown:
xmlns:xfdl="http://www.ibm.com/xmlns/prod/XFDL/7.0"
xmlns:custom="http://www.ibm.com/xmlns/prod/XFDL/Custom"
Each namespace declaration defines both a prefix and a URI for the namespace. In
this sample, the prefix for the XFDL namespace is xfdl and the URI is
http://www.ibm.com/xmlns/prod/XFDL/7.0.
Tags within the form are assigned specific namespaces by using the defined prefix.
For example, to declare that an option was in the custom namespace you would
use the prefix custom as shown:
<field sid="testField">
<custom:custom_option>value</custom:custom_option>
</field>
Function
Function IsXFDL() As Boolean
Parameters
There are no parameters for this function.
Returns
True if the node belongs to the XFDL namespace, False if it does not, or throws an
exception if an error occurs.
Example
The following function uses GetChildren and GetNext to walk through an entire
form and deletes all information that is not in the XFDL namespace. The function
uses IsXFDL to determine which nodes are in the XFDL namespace. Note that the
function assumes that you are passing the root node of the form on the first call.
Subsequent calls occur through recursion, which may provide any level of node.
Sub DeleteCustomInfo(Node)
Dim MainNode, TestNode ’ objects
Dim TempInt
’ Set the MainNode to be the child of the provided node.
Set MainNode = Node.GetChildren
’ Use recursion to step through each node in the form. This routine
’ walks to the last node in each page, then traverses back up the tree,
’ deleting nodes that are not in the XFDL namespace as it goes.
Do While (Not(MainNode Is Nothing))
Set TestNode = MainNode.getNext
DeleteCustomInfo(MainNode)
Set MainNode = TestNode
Loop
84
’ Check to see if the node passed to the routine is in the XFDL
’ namespace. If not, delete the node.
If Node.isXFDL = False Then
Node.Destroy
End If
End Sub
RemoveAttribute
Description
This function removes a specific attribute from a node. For example, the following
XFDL represents a value node:
<value custom:myAtt="x"></value>
To remove the custom attribute from this node, you would use removeAttribute.
Function
Sub RemoveAttribute(
theNamespaceURI As String,
theAttribute As String)
Parameters
Expression Type Description
theNamespaceURI String The namespace URI for the attribute. For
example:
http://www.ibm.com/xmlns/prod/XFDL/7.0
theAttribute String The local name of the attribute. For example,
compute, encoding, and so on.
Returns
Nothing or throws an exception if an error occurs.
Notes
Attributes and the Null Namespace
If an attribute is on a node in a non-XFDL namespace, and that attribute has no
namespace prefix, then the attribute is in the null namespace. For example, the
following node is the custom namespace, as is the first attribute, but since the
second attribute does not have a namespace prefix, it is in the null namespace:
<custom:processing custom:stage="2" user="tjones">
When an attribute is the null namespace, you may either provide a null value for
the namespace URI or use the namespace URI for the containing element.
For example, to indicate user attribute on the processing node, you could use the
null namespace or the custom namespace URI.
Attributes and Namespace Prefixes
The FormNodeP Functions 85
If you refer to an attribute with a namespace prefix, RemoveAttribute first looks
for a complete match, including both prefix and attribute name. If it does not find
such a match, it will look for a matching attribute name that has no prefix but
whose containing element has the same namespace.
For example, assume that the custom namespace and the test namespace both
resolve to the same URI. In the following case, looking for the id attribute would
locate the second attribute (test:id), since it has an explicit namespace declaration:
<a xmlns:custom="ABC" xmlns:test="ABC">
<custom:myElement id="1" test:id="2">
</a>
However, in the next case, the id attribute does not have an explicit namespace
declaration. Instead, it inherits the custom namespace. However, since the inherited
namespace resolves to the same URI, the id attribute is still located:
<custom:myElement id="1">
Example
The following function uses DereferenceEx to locate a custom node in the form. It
then uses RemoveAttribute to delete the ″stage″ attribute from the node, and calls
SetAttribute to update the value of the status attribute to ″completed″.
Sub CompletedProcessing(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Dereference the custom processing node in the global item.
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"global.global.custom:processing", 0, UFL_OPTION_REFERENCE, _
Nothing)
’ Remove the "stage" attribute from the node.
TempNode.RemoveAttribute vbNullString, "stage"
’ Update the status attribute to "completed".
TempNode.SetAttribute vbNullString, "status", "completed"
End Sub
RemoveEnclosure
Description
This function will either remove an enclosure from a specific datagroup or delete
the enclosure from the form. Call this function on the IFormNodeP that contains
the enclosure you want to remove.
Function
Sub RemoveEnclosure(
theDataGroup As String)
86
Parameters
Expression Type Description
theDataGroup String The datagroup that contains the enclosed item. If
null, the item will be removed from all
datagroups. If an item no longer belongs to any
datagroups, it is deleted from the form.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Example
The following function locates an attachment in a form an deletes it. First, the
function uses DereferenceEx to locate the node that contains the attachment. Next,
the function calls RemoveEnclosure to delete the attachment.
Sub DeleteAttachment(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Locate the PAGE3.DATA1 item, which contains the enclosure
Set TempNode = TempNode.DereferenceEx(vbNullString, "PAGE3.DATA1", _
0, UFL_ITEM_REFERENCE, Nothing)
’ Delete the enclosure
TempNode.RemoveEnclosure vbNullString
End Sub
ReplaceXFormsInstance
Description
This function either inserts or replaces an XForms instance in a form’s data model.
The instance can come from either from either a file or a memory block.
Call this function on the root node of the form or an instance node.
Use caution when calling this function. It can be used to overwrite signed instance
data.
Note: This function automatically updates the XForms data model.
Function
Sub ReplaceXformsInstance(
theModelID As String,
theNodeRef As String,
theNSNode As IFormNodeP,
theFilename As String,
theMemoryBlock As Variant
replaceRef As Boolean)
The FormNodeP Functions 87
Parameters
Expression Type Description
theModelID String The ID of the affected model. You must
use vbnullstring to use the default
model.
theNodeRef String An XPath reference to the instance (or
portion of an instance) you want to
replace. An empty string indicates the
default instance of the selected model.
theNSNode IFormNodeP A node that inherits the namespaces
used in the reference. This node defines
the namespaces for the function. Use
nothing if the node that this function is
operating on has inherited the necessary
namespaces.
theFilename String The file to read the instance from.
theMemoryBlock Variant The memory block that contains the
instance if you are not reading from a
file, input stream, or Reader. Use
nothing if theFilename is used.
replaceRef Boolean If True, the node specified by theNodeRef
is replaced with data. If False, the data
is appended as the last child of the
instance node.
Returns
Nothing if call is successful or throws an exception if an error occurs. .
Example
The following example shows a routine that replaces an XForms instance.
Sub SaveDataInstance(Form)
Form.ReplaceXFormsInstance "model1",
"instance(’instance1’)loanrecord.user_personal_info",
Nothing, "c:\InstanceData.xml", Nothing, True
End Sub
SetActiveForComputationalSystem
Description
This function sets whether the computational system is active. When active, all
computes in the form are evaluated on an on-going basis. When inactive, no
computes are evaluated.
Note that turning the computational system on causes all computes in the form to
be re-evaluated, which can be time consuming.
Function
Sub SetActiveForComputationalSystem(
activeFlag As Boolean)
88
Parameters
Expression Type Description
activeFlag Boolean Set to True to activate the compute system or
False to deactivate the compute system.
Returns
Nothing or throws an exception if an error occurs.
Example
The following function uses SetActiveForComputationalSystem to turn the
compute system off before making a series of changes to a form. Once the changes
are complete, SetActiveForComputationalSystem is called again to turn the
compute systems back on, allowing the form to update itself based on the changes
that were made.
Sub ProcessForm(Form)
’ Turn the compute system off. This allows us to make many changes to
’ the form quickly without the compute system slowing down the
’ processing.
Form.SetActiveForComputationalSystem(False)
’ Call a function that adds a series of new items to the form.
AddInformation(Form)
’ Call a function that removes a series of items from the form.
RemoveInformation(Form)
’ Call a function that updates some information in the form.
UpdateInformation(Form)
’ Turn the compute system back on so that the form can update itself.
Form.SetActiveForComputationalSystem(True)
End Sub
SetAttribute
Description
This function sets the value of a specific attribute for a node. For example, the
following XFDL represents a value node:
<value custom:myAtt="x"></value>
To change the custom attribute, you would use setAttribute. If the attribute does
not already exist, setAttribute will create it and assign the appropriate value.
Note: Do not use SetAttribute to set the compute attribute. Instead, use
SetFormula.
The FormNodeP Functions 89
Function
Sub SetAttribute(
theNamespaceURI As String,
theName As String,
theValue As String)
Parameters
Expression Type Description
theNamespaceURI String The namespace URI for the attribute. For
example:
http://www.ibm.com/xmlns/prod/XFDL/7.0
theAttribute String The local name of the attribute. For example,
encoding.
theValue String The value to assign to the attribute.
Returns
Nothing or throws an exception if an error occurs.
Notes
Attributes and the Null Namespace
If an attribute is on a node in a non-XFDL namespace, and that attribute has no
namespace prefix, then the attribute is in the null namespace. For example, the
following node is the custom namespace, as is the first attribute, but since the
second attribute does not have a namespace prefix, it is in the null namespace:
<custom:processing custom:stage="2" user="tjones">
When an attribute is the null namespace, you may either provide a null value for
the namespace URI or use the namespace URI for the containing element.
For example, to indicate user attribute on the processing node, you could use the
null namespace or the custom namespace URI.
Attributes and Namespace Prefixes
If you refer to an attribute with a namespace prefix, SetAttribute first looks for a
complete match, including both prefix and attribute name. If it does not find such
a match, it will look for a matching attribute name that has no prefix but whose
containing element has the same namespace.
For example, assume that the custom namespace and the test namespace both
resolve to the same URI. In the following case, looking for the id attribute would
locate the second attribute (test:id), since it has an explicit namespace declaration:
<a xmlns:custom="ABC" xmlns:test="ABC">
<custom:myElement id="1" test:id="2">
</a>
However, in the next case, the id attribute does not have an explicit namespace
declaration. Instead, it inherits the custom namespace. However, since the inherited
namespace resolves to the same URI, the id attribute is still located:
<custom:myElement id="1">
90
Example
The following function uses DereferenceEx to locate a custom node in the form. It
then uses RemoveAttribute to delete the ″stage″ attribute from the node, and calls
SetAttribute to update the value of the status attribute to ″completed″.
Sub CompletedProcessing(Form)
Dim TempNode ’ object
Set TempNode = Form
’ Dereference the custom processing node in the global item.
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"global.global.custom:processing", 0, UFL_OPTION_REFERENCE, _
Nothing)
’ Remove the "stage" attribute from the node.
TempNode.RemoveAttribute vbNullString, "stage"
’ Update the status attribute to "completed".
TempNode.SetAttribute vbNullString, "status", "completed"
End Sub
SetFormula
Description
This function sets the formula for a node.
Function
Sub SetFormula(
theComputation As String)
Parameters
Expression Type Description
theFormula String The formula to assign to the aNode. If null, the
formula is assigned as null.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Example
The following function sets the formula in a field so that it will copy a value from
another item in the form. First, the function uses DereferenceEx to locate the field.
The function then calls SetFormula to set the field to copy the value of another
field.
Sub AddFormula(Form)
Dim TempNode ’ object
Set TempNode = Form
The FormNodeP Functions 91
’ Locate the value node for the NameLabel on page 1.
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameLabel.value", 0, UFL_OPTION_REFERENCE, Nothing)
’ Set a formula for the node that will copy the value of the NameField
’ into the NameLabel.
TempNode.SetFormula "NameField.value"
End Sub
SetLiteralByRefEx
Description
This function finds a particular IFormNodeP as specified by a reference string.
Once the IFormNodeP is found, its literal will be set as specified. If the
IFormNodeP does not exist, this function will create it, but only if the IFormNodeP
would be an option or argument node.
If necessary, this function can create several nodes at once. For example, if you set
the literal for the second argument of an itemlocation, this function will create the
itemlocation option node and the two argument nodes and then set the literal for
the second argument node.
This function cannot create a IFormNodeP at the form, page, or item level; to do
so, use Create.
The node you call this function on is used as the starting point for the search.
Note: It is not necessary to call this function when you are using XForms. The
ReplaceXFormsInstance and ExtractXFormsInstancefunctions perform this
task automatically.
Function
Sub SetLiteralByRefEx(
theScheme As String,
theReference As String,
theReferenceCode As Long,
theCharSet As String,
theNSNode As IFormNodeP,
theLiteral As String)
Parameters
Expression Type Description
theScheme String Reserved. This must be null.
theReference String A string that contains the reference.
theReferenceCode Long Reserved. Must be 0.
theCharSet String The character set in which theLiteral parameter
is written. . Use null for ANSI/Unicode. Use
Symbol for Symbol.
92
Expression Type Description
theNSNode IFormNodeP A node that is used to resolve the namespaces
in theReference parameter (see “Determining
Namespace” on page 93). Use null if the node
that you are calling this function on has
inherited the necessary namespaces.
theLiteral String The string that will be assigned to the literal. If
null, any existing literal is removed.
Returns
Nothing if the call is successful or throws an exception if an error occurs.
Notes
IFormNodeP
Before you decide which IFormNodeP to use this function on, be sure you
understand the following:
1. The IFormNodeP you supply can never be more than one level in the hierarchy
above the level at which your reference string starts. For example, if the
reference string begins with an option, then the IFormNodeP can be no higher
in the hierarchy than an item.
2. If the IFormNodeP is at the same level or lower in the hierarchy than the
starting point of the reference string, the function will attempt to locate a
common ancestor. The function will locate the ancestor of the IFormNodeP that
is one level in the hierarchy above the starting point of the reference string. The
function will then attempt to follow the reference string back down through the
hierarchy. If the reference string cannot be followed from the located ancestor
(for example, if the ancestor is not common to both the IFormNodeP and the
reference string), the function will fail. For example, given a IFormNodeP that
represents ″field_1″ and a reference of ″field_2″, the function will access the
″page″ node above ″field_1″, and will then try to locate ″field_2″ below that
node. If the two fields were not on the same page, the function would fail.
Creating a Reference String
For more information about creating a reference, see “References” on page 6.
Digital Signatures
Do not set a node that is digitally signed. Doing so will break the digital signature
and produce an error.
Determining Namespace
In some cases, you may want to use the SetLiteralByRefEx function to set the
value for a node that does not have a globally defined namespace. For example,
consider the following form:
<label sid="Label1">
<value>Field1.processing:myValue</value>
</label>
The FormNodeP Functions 93
<field sid="Field1" xmlns:processing="URI">
<value></value>
<processing:myValue>10<processing:myValue>
</field>
In this form, the processing namespace is declared in the Field1 node. Any elements
within Field1 will understand that namespace; however, elements outside of the
scope of Field1 will not.
In cases like this, you will often start your search at a node that does not
understand the namespace of the node you are trying to locate. For example, you
might want to locate the node referenced in the value of Label1. In this case, you
would first locate the Label1 value node and get its literal. Then, from the Label1
value node, you would attempt to locate the processing:myValue node as shown:
Label1Node.SetLiteralByRefEx(vbNullString, "Field1.processing:myValue",
0, vbNullString, vbNullString, "20")
In this example, the setLiteralByRef function would fail. The function cannot
properly resolve the processing namespace because this namespace is not defined
for the Label1 value node. To correct this, you must also provide a node that
understands the processing namespace (in this case, any node in the scope of Field1)
as a parameter in the function:
Label1Node.SetLiteralByRefEx(vbNullString, "Field1.processing:myValue",
0, vbNullString, Field1Node, "20")
Example
The following example adds a label to a form. A node is passed into the function,
which then uses GetLiteralByRefEx to read the value of a field. The function then
uses DereferenceEx to locate the field node, and creates a label node as a sibling
using Create. Finally, the function creates a value for the new label node using
SetLiteralByRef.
Sub AddLabel(Form)
Dim TempNode, XFDL ’ objects
Dim Name ’ strings
Set TempNode = Form
’ Get the value of the NameField.value option node
Name = TempNode.GetLiteralByRefEx(vbNullString, _
"PAGE1.NameField.value", 0, vbNullString, Nothing)
’ Locate the NameField item node in the first page of the form
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameField", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get an XFDL object
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Create a label. This label is created as a sibling of the NameField,
’ and is named NameLabel.
Set TempNode = XFDL.Create(TempNode, UFL_AFTER_SIBLING, "label", _
vbNullString, vbNullString, "NameLabel")
’ Create a value option for the label. This option is assigned the
’ value of Name (as read from the field)
94
TempNode.SetLiteralByRefEx vbNullString, "value", 0, vbNullString, _
Nothing, Name
End Sub
SetLiteralEx
Description
This function sets the literal of a node. You should only set the literal for option or
argument nodes.
Note: It is not necessary to call this function when you are using XForms. The
ReplaceXFormsInstance and ExtractXFormsInstancefunctions perform this
task automatically.
Function
Sub SetLiteralEx(
theCharSet As String,
theLiteral As String)
Parameters
Expression Type Description
theCharSet String The character set in which theLiteral parameter is
written. . Use null for ANSI/Unicode. Use
Symbol for Symbol.
theLiteral String The literal to assign to the node. If null, any
existing literal is removed.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Notes
Digital Signatures
Do not set the literal of a node that has already been signed. Doing so will break
the digital signature and produce an error.
Example
The following function copies the value from one field to another. First, the
function uses DeferenceEx to locate the value node of a field on page one and
reads the value using GetLiteral. Next, the function locates a value node on page
two and writes the literal to that field using SetLiteralEx.
Sub CopyValue(Form)
Dim TempNode ’ object
Dim theName ’ string
Set TempNode = Form
’ Locate the NameField on page 1
The FormNodeP Functions 95
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameField.value", 0, UFL_OPTION_REFERENCE, Nothing)
’ Get the literal from the value node
theName = TempNode.GetLiteral
’ Locate the NameField on page 2
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE2.NameField.value", 0, UFL_OPTION_REFERENCE, Nothing)
’ Write the literal that was read from the first value node
TempNode.SetLiteralEx vbNullString, theName
End Sub
SignForm
Description
This function takes a button node and creates a digital signature for that button.
The signature is created using the signature filter in the button and the private key
of the signer.
Function
Function SignForm(
signer As ICertificate,
theInfo As IStringDictionary,
theStatus As Long
) As ISignature
Parameters
Expression Type Description
theSigner ICertificate The certificate to use to create the signature.
theInfo IStringDictionary Always use a null value.
theStatus Long This is a status flag that reports whether the
operation was successful. Possible values are:
SUSTATUS_OK — the operation was successful.
SUSTATUS_CANCELLED — the operation was
cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the
operation required user input, but could not
receive it (for example, it was run on a server
with no user).
Returns
A signature object if the call is successful, or throws an exception if an error occurs.
Example
The following function uses DereferenceEx to locate a signature button in the
form. It then calls GetCertificateList to get a list of valid certificates for that
96
button. The function then loops through the available certificates, using
GetDataByPath to check the common name of each certicate. When it finds the
certificate with the common name of ″TJones″, it calls SignForm and uses that
certificate to sign the form.
Sub ApplySignature(Form)
Dim SigNode, SigObject ’ objects
Dim TheCerts ’ CertificateList
Dim CommonName ’ String
Dim Cert ’ ICertificate
’ Get the SignatureButton node
Set SigNode = Form.DereferenceEx(vbNullString, _
"PAGE1.SignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get available certificates for that button
Set TheCerts = SigNode.GetCertificateList(vbNullString, 1) ’vbNull
’ Test each of the available certificates to see if it has a common
’ name of "TJones". If it does, use that certificate to sign
’ the form.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
Response.Write CommonName & vbCrLf
If CommonName = "TJones" Then
Set SigObject = SigNode.SignForm(TheCerts(1), Nothing, 1)
’ vbNull
End If
Next
End Sub
UpdateXFormsInstance
Description
This function supplants replaceXFormsInstance. It allows developers to insert data
anywhere within the XForms instance data, or replace it entirely. The instance can
come from either from either a file or a memory block. The UpdateXFormsInstance
function automatically updates the XForms data model.
Call this function on the root node of the form or an instance node.
Use caution when calling this function. It can be used to overwrite signed instance
data.
Note: This function automatically updates the XForms data model.
Function
Sub UpdateXformsInstance(
theModelID As String,
theNodeRef As String,
theNSNode As IFormNodeP,
theFilename As String,
theMemoryBlock As Variant,
updateType As Long)
The FormNodeP Functions 97
Parameters
Expression Type Description
theModelID String The ID of the affected model. You must
use vbnullstring to use the default
model.
theNodeRef String An XPath reference to the instance (or
portion of an instance) you want to
insert data into or replace. An empty
string indicates the default instance of
the selected model.
theNSNode IFormNodeP A node that inherits the namespaces
used in the reference. This node defines
the namespaces for the function. Use
nothing if the node that this function is
operating on has inherited the necessary
namespaces.
theFilename String The file to read the instance data from.
Note that if both a file and a memory
block are provided, the file will take
precedence.
theMemoryBlock Variant The memory block that contains the
instance if you are not reading from a
file, input stream, or Reader. Use
nothing if theFilename is used.
updateType Long Indicates which type of update to
perform:
XFORMS_UPDATE_REPLACE —
Replaces the specified data element.
XFORMS_UPDATE_APPEND — Adds
the data to the end of the specified data
instance or element as a child element.
XFORMS_UPDATE_INSERT_BEFORE
— Adds the data as a sibling of the
specified element. This sibling is placed
before the specified element.
Returns
Nothing if call is successful or throws an exception if an error occurs. .
Example
The following example shows a routine that replaces an XForms instance.
Sub SaveDataInstance(Form)
Form.UpdateXFormsInstance "model1",
"instance(’instance1’)loanrecord.user_personal_info",
Nothing, "c:\InstanceData.xml", Nothing, True, XFORMS_UPDATE_REPLACE)
End Sub
98
ValidateHMACWithSecret
Description
This function determines whether an HMAC signature is valid. HMAC signatures
include both Authenticated Clickwrap and Signature Pad signatures.
For Authenticated Clickwrap signatures, you must know the signer’s shared secret
to use this function. For Signature Pad signatures, you may use this function
without the shared secret if the signature was created without one. In any case, the
shared secret should be available from a corporate database or other system.
This function will also notarize (that is, digitally sign) a valid HMAC signature if
you provide a digital certificate. However, notarization will not occur if the
signature does not include a shared secret. Once notarized, you must use the
VerifySignature function to validate the signature.
Note: Authenticated Clickwrap is a separately licensed product. Please ensure that
your company has the license to use Authenticated Clickwrap before you
provide forms or functionality that rely on it.
Function
Function ValidateHMACWithSecret(
theSecret As String,
theServerCert As ICertificate,
theStatus As Long
) As Integer
Parameters
Expression Type Description
theSecret String The shared secret that identifies the user. This
should be available from a corporate database
or other system.
If there is more than one shared secret, you
must concatenate the strings with no
separating characters. For example, if the
secrets were ″blue″ and ″red″, you would pass
″bluered″ to the function.
If there is no shared secret pass an empty
string.
theServerCert ICertificate The server certificate. If the HMAC signature
is valid, the function will use the private key
of this certificate to digitally sign the HMAC
signature. This signature is appended to the
signature item, and can be verified using
VerifySignature.
If you pass null, the function will simply
validate the HMAC signature.
The FormNodeP Functions 99
Expression Type Description
theStatus Long This is a status flag that reports whether the
operation was successful. Possible values are:
SUSTATUS_OK — the operation was
successful.
SUSTATUS_CANCELLED — the operation
was cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the
operation required user input, but could not
receive it (for example, it was run on a server
with no user).
Returns
:A constant if the verification is successful, or throws an exception if an error
occurs. The following table lists the possible return values:
Code
Numeric
Value Status
UFL_DS_OK 0 The signature is verified.
UFL_DS_ALGORITHM UNAVAILABLE 13590 The appropriate verification
engine for the signature is not
available.
UFL_DS_F2MATCHSIGNER 13529 The certificate does not match
the signer’s name.
UFL_DS_FAILED AUTHENTICATION 1272 The signature is invalid or the
secret used is incorrect.
UFL_DS_HASHCOMPFAILED 13527 The document has been
tampered with.
UFL_DS_NOSIGNATURE 13526 There is no signature.
UFL_DS_NOTAUTHENTICATED 1240 The signer cannot be
authenticated.
UFL_DS_UNEXPECTED 13589 An unexpected error occurred.
UFL_DS_UNVERIFIABLE 859 The signature cannot be
verified.
Example
The following function uses DereferenceEx and GetLiteralByRefEx to locate the
signature item in a form. It then uses GetEngineCertificateList and
GetDataByPath to locate a server signing certificate. Next, it uses GetSignature
and GetDataByPath to get the signer’s common name. Finally, it uses
ValidateHMACWithSecret to determine if the HMAC signature is valid, and
returns ″Valid″ or ″Invalid″, as appropriate.
Function ValidateHMACSig(Form)
Dim SigObject, XFDL ’ Objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, CommonName, SigItemRef ’ Strings
Dim Validation ’ Integer
100
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret,
’ and sets SharedSecret to match. In most cases, this would be a
’ database lookup. For the purposes of this example, we will simply
’ assign a value to SharedSecret.
SharedSecret = "secret"
’ Validate the signature
Validation = SigNode.ValidateHMACWithSecret(SharedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSig = "Valid"
Else
ValidateHMACSig = "Invalid"
End If
End Function
The FormNodeP Functions 101
ValidateHMACWithHashedSecret
Description
This function determines whether an HMAC signature is valid. HMAC signatures
include both Authenticated Clickwrap and Signature Pad signatures.
For Authenticated Clickwrap signatures, you must know the hash of the signer’s
shared secret to use this function. For Signature Pad signatures, you may use this
function without the shared secret if the signature was created without one. In any
case, the shared secret should be available from a corporate database or other
system.
This function will also notarize (that is, digitally sign) a valid HMAC signature if
you provide a digital certificate. However, notarization will not occur if the
signature does not include a shared secret. Once notarized, you must use the
VerifySignature function to validate the signature.
Note: Authenticated Clickwrap is a separately licensed product. Please ensure that
your company has the license to use Authenticated Clickwrap before you
provide forms or functionality that rely on it.
Function
Function ValidateHMACWithHashedSecret(
hashedSecret As Variant,
theServerCert As ICertificate,
theStatus As Long
) As Integer
102
Parameters
Expression Type Description
hashedSecret Variant The hash of the shared secret that identifies
the user. This should be available from a
corporate database or other system.
If there is more than one shared secret, you
must concatenate the strings with no
separating characters and then hash the
combined secret. For example, if the secrets
were ″blue″ and ″red″, you would pass the
hash of ″bluered″ to the function.
If there is no shared secret, pass and empty
string.
You must encode the byte array as follows:
Authenticated Clickwrap (HMAC) UTF-8
Signature Pad UTF-16LE
The method for doing this depends on the
software library you are using to interface
with the COM API.
Note that the function expects the hashed
secret to be a single-byte binary array. Using a
double-byte binary array produces an
incorrect result.
theCertificate ICertificate The server certificate. If the HMAC signature
is valid, the function will use the private key
of this certificate to digitally sign the HMAC
signature. This signature is appended to the
signature item, and can be verified using
UFLVerifySignature.
If you pass null, the function will simply
validate the HMAC signature.
theStatus Long This is a status flag that reports whether the
operation was successful. Possible values are:
SUSTATUS_OK — the operation was
successful.
SUSTATUS_CANCELLED — the operation
was cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the
operation required user input, but could not
receive it (for example, it was run on a server
with no user).
Returns
A constant if the verification is successful, or throws an exception if an error
occurs. The following table lists the possible return values:
The FormNodeP Functions 103
Code
Numeric
Value Status
UFL_DS_OK 0 The signature is verified.
UFL_DS_ALGORITHM UNAVAILABLE 13590 The appropriate verification
engine for the signature is
not available.
UFL_DS_F2MATCHSIGNER 13529 The certificate does not
match the signer’s name.
UFL_DS_FAILED AUTHENTICATION 1272 The signature is invalid or
the secret used is incorrect.
UFL_DS_HASHCOMPFAILED 13527 The document has been
tampered with.
UFL_DS_NOSIGNATURE 13526 There is no signature.
UFL_DS_NOT AUTHENTICATED 1240 The signer cannot be
authenticated.
UFL_DS_UNEXPECTED 13589 An unexpected error
occurred.
UFL_DS_UNVERIFIABLE 859 The signature cannot be
verified.
Example
The following function validates an HMAC signature using a hashed secret. First,
the function uses DereferenceEx and GetLiteralByRefEx to locate the signature
item in a form. It then uses GetEngineCertificateList and GetDataByPath to locate
a server signing certificate. Next, it uses GetSignature and GetDataByPath to get
the signer’s common name and Hash to create a hashed secret. Finally, it uses
ValidateHMACWithHashedSecret to determine if the HMAC signature is valid,
and returns ″Valid″ or ″Invalid″, as appropriate.
Note that this example also relies on a second function called StringToBinary. This
function converts a string to a single-byte binary array, which is required for the
hash function. This prevents COM from converting the string to a double-byte
array before hashing it, which would produce an incorrect result.
Function ValidateHMACSigHashed(Form)
Dim SigObject, XFDL, HashObject, SecurityManager ’ objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, HashedSecret, CommonName, _
SigItemRef ’ Strings
Dim Validation ’ Integer
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
104
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret
’ that is hashed, and sets SharedSecret to match. In most cases, this
’ would be a database lookup. For the purposes of this example, we will
’ use the Hash function to assign a hashed value to HashedSecret.
’ Get the Security Manager object
Set SecurityManager = _
CreateObject("PureEdge.security_SecurityManager")
’ Get the Hash object
Set HashObject = SecurityManager.LookupHashAlgorithm("sha1")
’ Set the Hashed secret. First convert the secret to a single-byte
’ binary array, then hash the secret.
SharedSecret = StringToBinary("secret")
HashedSecret = HashObject.Hash(SharedSecret)
’ Validate the signature
Validation = SigNode.ValidateHMACWithHashedSecret(HashedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSigHashed = "Valid"
Else
ValidateHMACSigHashed = "Invalid"
End If
End Function
’ The following function is required to convert a string to a single-byte binary
’ array before hashing that string. This prevents COM from converting
’ the string to a multi-byte format, which would produce and incorrect
The FormNodeP Functions 105
’ hash.
Function StringToBinary(String)
Dim Counter, Binary
For Counter = 1 to len(String)
Binary = Binary & ChrB(Asc(Mid(String, Counter, 1)))
Next
StringToBinary = Binary
End Function
VerifyAllSignatures
Description
This function verifies the correctness of all digital signatures in a given form whose
root node is provided. It finds all items of type signature and calls VerifySignature
for each signature. Errors are logged for all invalid signatures.
This function checks the following conditions for each signature:
v The signature item contains mimedata.
v The mimedata contains a hash value and signer certificate.
v The signer certificate contains the same ID as that recorded in the signature
item’s signer option.
v The signer certificate has not expired.
Function
Function VerifyAllSignatures(
reportAsErrorsFlag As Boolean
) As Integer
Parameters
Expression Type Description
reportAsErrorsFlag Boolean Set to True if you want errors about the
signatures to be reported by throwing an
exception, or False if you want the error
code to be only returned through the return
value.
Returns
An integer having one of the following values:
Code Status
UFL_SIGS_OK The signatures are valid.
UFL_SIGS_NOTOK One or more signatures are broken.
UFL_SIGS_UNVERIFIED One or more signatures are unverifiable.
If one or more of the signatures is not valid and the reportAsErrorsFlag is true, an
exception is thrown. On error, the function throws an exception.
106
Example
The following example uses VerifyAllSignatures to check all of the signatures in
the form, then returns ″Valid″ if the signatures are okay or ″Invalid″ if they are not.
Function CheckAllSignatures(Form)
Dim Status ’ Integer
Status = Form.VerifyAllSignatures(False)
If Status = UFL_SIGS_OK Then
CheckAllSignatures = "Valid"
Else
CheckAllSignatures = "Invalid"
End If
End Function
VerifySignature
Description
This function verifies the correctness of the given digital signature. You supply the
root of the form that contains the signature you want to verify. This function
checks the following conditions:
v The signature item contains mimedata.
v The mimedata contains a hash value and signer certificate.
v The signer certificate contains the same ID as that recorded in the signature
item’s signer option.
v The signer certificate has not expired.
A plain text representation of the form (filtered by the signature item’s filter) is
constructed and the result is hashed. This hash value must match the hash value
stored in the signature.
Function
Function VerifySignature(
signatureItem As IFormNodeP,
theCertChain As String,
reportAsErrorsFlag As Boolean
) As Integer
Parameters
Expression Type Description
signatureItem IFormNodeP The signature to verify.
theCertChain String Reserved. Must be null.
reportAsErrorsFlag Boolean Set to True if you want errors about the
signatures to be reported by throwing an
exception or False if you want the error
code to be returned through the return
value.
Returns
A Long having one of the following values, depending on the status of the
signature:
The FormNodeP Functions 107
Code Status
UFL_DS_OK The signature is verified.
UFL_DS_ALGORITHMUNAVAILABLE The appropriate verification
engine for the signature is not
available.
UFL_DS_CERTEXPIRED The certificate has expired.
UFL_DS_CERTNOTFOUND The certificate cannot be located.
UFL_DS_CERTNOTTRUSTED The certificate is not trusted.
UFL_DS_CERTREVOKED The certificate has been revoked.
UFL_DS_CRLINVALID The certificate revocation list is
invalid.
UFL_DS_F2MATCHSIGNER The certificate does not match the
signer’s name.
UFL_DS_HASHCOMPFAILED The document has been tampered
with.
UFL_DS_ISSUERCERTEXPIRED The issuer’s certificate has
expired.
UFL_DS_ISSUERINVALID The issuer is invalid for the
certificate used to sign.
UFL_DS_ISSUERKEYUSAGE UNACCEPTABLE The issuer certificate’s key usage
extension does not match what
the key was used for.
UFL_DS_ISSUERNOTCA The certificate’s issuer is not a
Certificate Authority.
UFL_DS_ISSUERNOTFOUND The issuer’s certificate was not
located.
UFL_DS_ISSUERSIGFAILED Verification of the issuer’s
certificate failed.
UFL_DS_KEYREVOKED The key used to create the
signature has been revoked.
UFL_DS_KEYUSAGEUNACCEPTABLE The certificate’s key usage
extension does not match what
the key was used for.
UFL_DS_KRLINVALID The Key Revocation List is
invalid.
UFL_DS_NOSIGNATURE There is no signature.
UFL_DS_NOTAUTHENTICATED The signer cannot be
authenticated.
UFL_DS_POLICYUNACCEPTABLE The certificate’s policy extension
does not match the acceptable
policies.
UFL_DS_SIGNATUREALTERED The signature has been tampered
with.
UFL_DS_UNEXPECTED An unexpected error occurred.
UFL_DS_UNVERIFIABLE The signature cannot be verified.
If the signature is not valid and the reportAsErrorsFlag is True, an exception is
thrown. On error, the function throws an exception.
108
Example
The following function checks to see the signature in the form is valid. First, the
function uses DereferenceEx to locate the signature button. It then uses
GetLiteralByRefEx to get the name of the signature item, and uses another
DereferenceEx to locate that item. Next, it uses VerifySignature to determine
whether the signature is valid. If so, it return the string ″Valid″. If not, it uses
DeleteSignature to delete the signature and returns the string ″Invalid″.
Function CheckSignature(Form)
Dim TempNode, SigNode ’ objects
Dim SigStatus ’ Integer
Dim SigItemRef ’ Strings
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.SignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get a reference to the signature item from the signature option
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Verify the signature
SigStatus = Form.VerifySignature(SigNode, vbNullString, False)
’ If the signature is not verified, then delete the signature and set
’ the return code to "Invalid". Otherwise, set the return code to
’ "Valid".
If (Not(SigStatus = UFL_DS_OK)) Then
TempNode.DeleteSignature SigNode
CheckSignature = "Invalid"
Else
CheckSignature = "Valid"
End If
End Function
WriteForm
Description
This function will write a form to the specified file . Call this function on the root
node of the form. The version number of the form determines the format of the
output file. You can specify whether to compress the output file and whether to
observe the transmit and save settings in the form.
If no format is specified, the default is to write the form in the same format in
which it was read. If the form in question was created dynamically by your
application, WriteForm will, by default, write it as an XFDL form in uncompressed
format.
The FormNodeP Functions 109
Function
Sub WriteForm(
theFilePath As String,
triggerItem As IFormNodeP,
flags As Long)
Parameters
Expression Type Description
theFilePath String This is the path to the file on the local disk to
which the form will be written.
triggerItem IFormNodeP This is the item that caused the form to be
submitted. Set to null if the API receives the form
in a manner other than transmission.
flags Long The following flags are valid:
UFL_TRANSMIT_ALLOW allows the transmit
options (that is, transmitdatagroups, transmitgroups,
transmititemrefs, transmititems, transmitoptionrefs,
transmitpagerefs and transmitoptions) to control
which portions of the form are sent. Without this
flag, the entire form will be sent regardless of the
transmit options in the form.
UFL_SAVE_ALLOW allows the saveformat option
to specify what format the form should be saved
in. If no format is specified then the form will be
saved in the same format that it is read.
Note: Specify 0 if you do not want to enable any
of the transmit options.
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following example uses WriteForm to write the form in memory to a file on
the local drive.
Sub SaveForm(Form)
’ Write the form to a file on disk
Form.WriteForm "c:\testform.xfd", Nothing, 0
End Sub
WriteFormToASPResponse
Description
This function will write a form to the ASP response object. Call this function on the
root node of the form. The version number of the form determines the format of
the output file. You can specify whether to compress the output file and whether
to observe the transmit and save settings in the form.
110
If no format is specified, the default is to write the form in the same format in
which it was read. If the form in question was created dynamically by your
application, WriteFormToASPResponse will, by default, write it as an XFDL form
in uncompressed format.
Function
Sub WriteFormToASPResponse(
triggerItem As IFormNodeP,
flags As Long)
Parameters
Expression Type Description
triggerItem IFormNodeP This is the item that caused the form to be
submitted. Set to null if the API receives the form
in a manner other than transmission.
flags Long The following flags are valid:
UFL_TRANSMIT_ALLOW allows the transmit
options (that is, transmitdatagroups, transmitgroups,
transmititemrefs, transmititems, transmitoptionrefs,
transmitpagerefs and transmitoptions) to control
which portions of the form are sent. Without this
flag, the entire form will be sent regardless of the
transmit options in the form.
UFL_SAVE_ALLOW allows the saveformat option
to specify what format the form should be saved
in. If no format is specified then the form will be
saved in the same format that it is read.
Note: Specify 0 if you do not want to enable any of
the transmit options.
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following example uses WriteFormToASPResponse to write the form in
memory to the ASP response object.
Sub RespondWithForm(Form)
Form.WriteFormToASPResponse Nothing, 0
End Sub
XMLModelUpdate
Description
This function updates the XML data model in the form. This is necessary if
computes have changed the structure of the data model in some way, such as
changing or adding bindings. These sorts of changes do not take effect until the
XMLModelUpdate function is called.
The FormNodeP Functions 111
Function
Sub XMLModelUpdate()
Parameters
There are no parameters for this function.
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following example uses SetLiteralByRefEx to change a binding in the form, so
that it binds to a different option. It then calls XMLModelUpdate so that the data
model reflects the change.
Function ChangeBinding(Form)
’ Change the binding to a field on the second page.
Form.SetLiteralByRefEx vbNullString, _
"global.global.xmlmodel.bindings[0][boundoption]", 0, _
vbNullString, Nothing, "PAGE2.NameField.value"
’ Update the XML model.
Form.XMLModelUpdate
End Function
112
The Hash Functions
The Hash functions allow you to hash messages.
v To use the Hash functions you must import the IFS_COM_API type library, as
shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
Hash
Description
This function hashes a message using the hashing algorithm of your choice.
Function
Function Hash(
theMessage As Variant)
Parameters
Expression Type Description
theMessage Variant The message you want to hash.
Note that the function expects the hashed secret
to be a single-byte binary array. Using a
double-byte binary array will produce an
incorrect result.
Returns
A hashed message, or throws an exception if an error occurs.
Example
The following function validates an HMAC signature using a hashed secret. First,
the function uses DereferenceEx and GetLiteralByRefEx to locate the signature
item in a form. It then uses GetEngineCertificateList and GetDataByPath to locate
a server signing certificate. Next, it uses GetSignature and GetDataByPath to get
the signer’s common name and LookupHashAlgorith and Hash to create a hashed
secret. Finally, it uses ValidateHMACWithHashedSecret to determine if the
HMAC signature is valid, and returns ″Valid″ or ″Invalid″, as appropriate.
Note that this example also relies on a second function called StringToBinary. This
function converts a string to a single-byte binary array, which is required for the
hash function. This prevents COM from converting the string to a double-byte
array before hashing it, which would produce an incorrect result.
Function ValidateHMACSigHashed(Form)
Dim SigObject, XFDL, HashObject, SecurityManager ’ objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, HashedSecret, CommonName, _
SigItemRef ’ Strings
© Copyright IBM Corp. 2003, 2006 113
Dim Validation ’ Integer
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret
’ that is hashed, and sets SharedSecret to match. In most cases, this
’ would be a database lookup. For the purposes of this example, we will
’ use the Hash function to assign a hashed value to HashedSecret.
’ Get the Security Manager object
Set SecurityManager = _
CreateObject("PureEdge.security_SecurityManager")
’ Get the Hash object
Set HashObject = SecurityManager.LookupHashAlgorithm("sha1")
’ Set the Hashed secret. First convert the secret to a single-byte
’ binary array, then hash the secret.
SharedSecret = StringToBinary("secret")
HashedSecret = HashObject.Hash(SharedSecret)
’ Validate the signature
114
Validation = SigNode.ValidateHMACWithHashedSecret(HashedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSigHashed = "Valid"
Else
ValidateHMACSigHashed = "Invalid"
End If
End Function
’ The following function is required to convert a string to a single-byte ’
’ binary array before hashing that string. This prevents COM from converting
’ the string to a multi-byte format, which would produce an incorrect hash.
Function StringToBinary(String)
Dim Counter, Binary
For Counter = 1 to len(String)
Binary = Binary & ChrB(Asc(Mid(String, Counter, 1)))
Next
StringToBinary = Binary
End Function
The Hash Functions 115
116
The Initialization Functions
The initialization function provides an easy function for initializing the API.
v To use the Initialization function you must import the IFS_COM_API type
library, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
v To use the Initialization function, you must first create the PureEdge.DTK object,
as shown:
Set DTK = CreateObject("PureEdge.DTK")
You can then call the function on this object.
IFSInitialize
Description
This function initializes the API. The parameters specify which version of the API
your application should bind with (see the Notes below for more details).
You must call this function before calling any of the other functions in the API.
Function
Sub IFSInitialize(
progName As String,
progVer As String,
apiVer As String)
Parameters
Expression Type Description
progName String The name of the application calling IFSInitialize. This
name is used to identify the application within the .ini
file. It also sets the name that is returned by the XFDL
applicationName function.
progVer String The version number of the application calling
IFSInitialize. If the .ini file has an entry for this
version of the application, the application will bind to
the version of the API listed in that entry.
apiVer String The version number of the API the application should
use by default. If the .ini file does not contain an entry
for the specific application, the application will bind
to the API specified by this parameter.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Notes
About Binding Your Applications to the API
© Copyright IBM Corp. 2003, 2006 117
When you initialize the API, the IFSInitialize function determines which version of
the API to use based on the parameters you pass it. This allows you to exercise a
great deal of control over which version of the API is used by your applications,
and prevents the problems normally associated with common DLL files (often
referred to as ″DLL hell″).
IFSInitialize uses a configuration file to determine which version of the API will
bind to any application. This allows multiple versions of the API to co-exist on
your computer, and ensures that your applications use the correct version of the
API.
The configuration file is called PureEdgeAPI.ini and is installed with the API. Refer
to the IBM Workplace Forms Server — API Installation and Setup Guide for the exact
location of the file.
Note: You should redistribute the PureEdgeAPI.ini file with any applications that
use the API. See the IBM Workplace Forms Server — API Installation and
Setup Guide for more information about redistributing applications.
The configuration file contains a section for each application that might call the
API, plus a default ″API″ section. Each section contains a list of version numbers in
the following format:
<version of application> = <folder containing appropriate version of API>
For example, the configuration file might look like this:
[API]
5.1.0 = 51
5.0.0 = 50
[CustomApplication]
1.1.0 = 51
1.0.0 = 50
In this case, the folder indicated on the right hand side of each statement is part of
the relative path to the API, and assumes the API was installed in the default
folder. For example, under Windows ″50″ would resolve to:
c:\WinNT\System32\PureEdge\50
You can also specify an absolute path by placing a drive letter before the path. For
example, ″c:\50″ would resolve to:
c:\50\
When you initialize the API, you include three parameters in the initialization call:
v The name of your application (as it would appear in the configuration file).
v The version of your application.
v The version of the API that your application should bind to by default.
The initialization call will first check the configuration file to see if your
application is listed. For example, using the configuration file above, if you make
an initialization call for ″CustomApplication″ version ″1.1.0″, then the application
binds to the API in the ″51″ folder.
If your application is not listed in the configuration file, the initialization call uses
the default version of the API. For example, using the configuration file above, if
you declare ″5.1.0″ as the default API, then your application binds to the API in the
″51″ folder.
118
You can add your own entries to the configuration file before distributing it to
your customers, or you can rely on the default API entries.
Note: IFSInitialize was introduced for version 4.5.0 of the API. Binding does not
work in this manner for earlier versions of the API. Do not include earlier
versions of the API in the configuration file.
Example
In the example below, IFSInitialize initializes the API for the application called
aspApp.
Function LoadForm(FileName)
Dim DTK, XFDL, TempForm ’ objects
’ Get a DTK object and initialize the API
Set DTK = CreateObject("PureEdge.DTK")
DTK.IFSInitialize "aspApp", "1.0.0", "2.6.0"
’ Get an XFDL object and read the form from the supplied file
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TempForm = XFDL.ReadForm(FileName, 0)
’ Return the form
Set LoadForm = TempForm
End Function
IFSInitializeWithLocale
Description
This function initializes the API. The parameters specify the default locale, and
which version of the API your application should bind with (see the Notes below
for more details).
You must call this function before calling any of the other functions in the API.
Function
Sub IFSInitializeWithLocale(
progName As String,
progVer As String,
apiVer As String
theLocale As String)
Parameters
Expression Type Description
progName String The name of the application calling
IFSInitializeWithLocale. This name is used to identify
the application within the .ini file. It also sets the
name that is returned by the XFDL applicationName
function.
The Initialization Functions 119
Expression Type Description
progVer String The version number of the application calling
IFSInitializeWithLocale. If the .ini file has an entry
for this version of the application, the application will
bind to the version of the API listed in that entry.
apiVer String The version number of the API the application should
use by default. If the .ini file does not contain an entry
for the specific application, the application will bind
to the API specified by this parameter.
theLocale String The default locale of the application.
Returns
Nothing if call is successful or throws an exception if an error occurs.
Notes
About Binding Your Applications to the API
When you initialize the API, the IFSInitializeWithLocale function determines
which version of the API to use based on the parameters you pass it. This allows
you to exercise a great deal of control over which version of the API is used by
your applications, and prevents the problems normally associated with common
DLL files (often referred to as ″DLL hell″).
IFSInitializeWithLocale uses a configuration file to determine which version of the
API will bind to any application. This allows multiple versions of the API to
co-exist on your computer, and ensures that your applications use the correct
version of the API.
The configuration file is called PureEdgeAPI.ini and is installed with the API. Refer
to the IBM Workplace Forms Server — API Installation and Setup Guide for the exact
location of the file.
Note: You should redistribute the PureEdgeAPI.ini file with any applications that
use the API. See the IBM Workplace Forms Server — API Installation and
Setup Guide for more information about redistributing applications.
The configuration file contains a section for each application that might call the
API, plus a default ″API″ section. Each section contains a list of version numbers in
the following format:
<version of application> = <folder containing appropriate version of API>
For example, the configuration file might look like this:
[API]
2.6.1 = 70
2.6.0 = 70
[CustomApplication]
1.1.0 = 70
1.0.0 = 70
In this case, the folder indicated on the right hand side of each statement is part of
the relative path to the API, and assumes the API was installed in the default
folder. For example, under Windows “70” would resolve to:
120
C:\Program Files\IBM\Workplace Forms\Server\26\API\redist
\msc32\PureEdge\26
You can also specify an absolute path by placing a drive letter before the path. For
example, “c:\70” would resolve to:
c:\70\
When you initialize the API, you include three parameters in the initialization call:
v The name of your application (as it would appear in the configuration file).
v The version of your application.
v The version of the API that your application should bind to by default.
The initialization call will first check the configuration file to see if your
application is listed. For example, using the configuration file above, if you make
an initialization call for “CustomApplication” version “1.1.0”, then the application
binds to the API in the “70” folder.
If your application is not listed in the configuration file, the initialization call will
use the default version of the API. For example, using the configuration file above,
if you declare “2.6.1” as the default API, then your application binds to the API in
the “70” folder.
You can add your own entries to the configuration file before distributing it to
your customers, or you can rely on the default API entries.
Example
In the example below, IFSInitializeWithLocale initializes the API for the
application called aspApp.
Function LoadForm(FileName)
Dim DTK, XFDL, TempForm ’ objects
’ Get a DTK object and initialize the API
Set DTK = CreateObject("PureEdge.DTK")
DTK.IFSInitializeWithLocale "aspApp", "1.0.0",
"2.6.0", "fr-FR"
’ Get an XFDL object and read the form from the supplied file
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TempForm = XFDL.ReadForm(FileName, 0)
’ Return the form
Set LoadForm = TempForm
End Function
The Initialization Functions 121
122
The LocalizationManager Functions
The LocalizationManager functions control which language the API uses to report
errors.
v To use the LocalizationManager functions you must import the IFS_COM_API
type library, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
v To use the LocalizationManager function, you must first create the
PureEdge.i18n_LocalizationManager object, as shown:
Set theManager = CreateObject("PureEdge.i18n_LocalizationManager")
You can then call the function on this object.
GetCurrentThreadLocale
Description
This function returns which locale is in use for the current thread. This determines
what language the API uses when reporting errors. By default, the API uses the
default locale.
The API supports the following locales:
Language Locale Locale Name
Chinese Simplified Han, China zh-Hans-CN
Simplified Han, Singapore zh-Hans-SG
Traditional Han, Hong Kong S.A.R., China zh-Hant-HK
Traditional Han, Taiwan zh-Hant-TW
Croatian Croatia hr-HT
Czech Czech Republic cs-CZ
Danish Denmark da-DK
Dutch Belgium nl-BE
The Netherlands nl-NL
English Australia en-AU
Belgium en-BE
Canada en-Ca
Hong Kong S.A.R., China en-HK
India en-IN
Ireland en-IE
New Zealand en-NZ
Philippines en-PH
Singapore en-SG
South Africa en-ZA
United Kingdom en-GB
United States en-US
© Copyright IBM Corp. 2003, 2006 123
Language Locale Locale Name
Finnish Finland fi-FI
French Belgium fr-BE
Canada fr-CA
France fr-FR
Luxembourg fr-LU
Switzerland fr-CH
German Austria de-AT
Germany de-DE
Luxembourg de-LU
Switzerland de-CH
Greek Greece el-GR
Hungarian Hungary hu-HU
Italian Italy it-IT
Switzerland it-CH
Japanese Japan ja-JP
Korean South Korea ko-KR
Norwegian Bokmål Norway nb-NO
Polish Poland pl-PL
Portuguese Brazil pt-BR
Portugal pt-PT
Romanian Romania ro-RO
Russian Russian ru-RU
Slovak Slovakia sk-SK
Slovene Slovenia sl_SI
Spanish Argentina es-AR
Bolivia es-BO
Chile es-CL
Colombia es-CO
Costa Rica es-CR
Dominican Republic es-DO
Ecuador es-EC
El Salvador es-SV
Guatemala es-GT
Honduras es-HN
Mexico es-MX
Nicaragua es-NI
Panama es-PA
Paraguay es-PY
Peru es-PE
Puerto Rico es-PR
Spain es-ES
124
Language Locale Locale Name
United States es-US
Uruguay es-UY
Venezuela es-VE
Swedish Sweden sv-SE
Turkish Turkey tr-TR
The locale name consists of two parts: the language code and the country code, as
shown
<language code>_<COUNTRY CODE>
For example, to specify the Japanese locale, you would type:
jp_JP
If you need a more specific locale, you may add additional codes after the country
code. For example, to indicate French in France with a Euro dialect, you would
type:
fr_FR_EU
Function
Sub GetCurrentThreadLocale()
Parameters
There are no parameters for this function.
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following function calls GetCurrentThreadLocale to get the locale.
Function GetLanguage()
Dim theManager ’ object
Set theManager = CreateObject("PureEdge.i18n_LocalizationManager")
GetLanguage=theManager.GetCurrentThreadLocale
End Function
GetDefaultLocale
Description
This function returns the default locale the API uses when reporting errors.
The API supports the following locales:
Language Locale Locale Name
Chinese Simplified Han, China zh-Hans-CN
Simplified Han, Singapore zh-Hans-SG
The LocalizationManager Functions 125
Language Locale Locale Name
Traditional Han, Hong Kong S.A.R., China zh-Hant-HK
Traditional Han, Taiwan zh-Hant-TW
Croatian Croatia hr-HT
Czech Czech Republic cs-CZ
Danish Denmark da-DK
Dutch Belgium nl-BE
The Netherlands nl-NL
English Australia en-AU
Belgium en-BE
Canada en-Ca
Hong Kong S.A.R., China en-HK
India en-IN
Ireland en-IE
New Zealand en-NZ
Philippines en-PH
Singapore en-SG
South Africa en-ZA
United Kingdom en-GB
United States en-US
Finnish Finland fi-FI
French Belgium fr-BE
Canada fr-CA
France fr-FR
Luxembourg fr-LU
Switzerland fr-CH
German Austria de-AT
Germany de-DE
Luxembourg de-LU
Switzerland de-CH
Greek Greece el-GR
Hungarian Hungary hu-HU
Italian Italy it-IT
Switzerland it-CH
Japanese Japan ja-JP
Korean South Korea ko-KR
Norwegian Bokmål Norway nb-NO
Polish Poland pl-PL
Portuguese Brazil pt-BR
Portugal pt-PT
Romanian Romania ro-RO
Russian Russian ru-RU
126
Language Locale Locale Name
Slovak Slovakia sk-SK
Slovene Slovenia sl_SI
Spanish Argentina es-AR
Bolivia es-BO
Chile es-CL
Colombia es-CO
Costa Rica es-CR
Dominican Republic es-DO
Ecuador es-EC
El Salvador es-SV
Guatemala es-GT
Honduras es-HN
Mexico es-MX
Nicaragua es-NI
Panama es-PA
Paraguay es-PY
Peru es-PE
Puerto Rico es-PR
Spain es-ES
United States es-US
Uruguay es-UY
Venezuela es-VE
Swedish Sweden sv-SE
Turkish Turkey tr-TR
The locale name consists of two parts: the language code and the country code, as
shown
<language code>_<COUNTRY CODE>
For example, to specify the Japanese locale, you would type:
jp_JP
If you need a more specific locale, you may add additional codes after the country
code. For example, to indicate French in France with a Euro dialect, you would
type:
fr_FR_EU
Function
Sub GetDefaultLocale()
Parameters
There are no parameters for this function.
The LocalizationManager Functions 127
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following function calls GetDefaultLocale to get the locale.
Function GetLanguage()
Dim theManager ’ object
Set theManager = CreateObject("PureEdge.i18n_LocalizationManager")
GetLanguage=theManager.GetDefaultLocale
End Function
SetCurrentThreadLocale
Description
This function sets which locale the API uses when reporting errors. By default, the
API uses the application’s default locale.
The API supports the following locales:
Language Locale Locale Name
Chinese Simplified Han, China zh-Hans-CN
Simplified Han, Singapore zh-Hans-SG
Traditional Han, Hong Kong S.A.R., China zh-Hant-HK
Traditional Han, Taiwan zh-Hant-TW
Croatian Croatia hr-HT
Czech Czech Republic cs-CZ
Danish Denmark da-DK
Dutch Belgium nl-BE
The Netherlands nl-NL
English Australia en-AU
Belgium en-BE
Canada en-Ca
Hong Kong S.A.R., China en-HK
India en-IN
Ireland en-IE
New Zealand en-NZ
Philippines en-PH
Singapore en-SG
South Africa en-ZA
United Kingdom en-GB
United States en-US
Finnish Finland fi-FI
French Belgium fr-BE
128
Language Locale Locale Name
Canada fr-CA
France fr-FR
Luxembourg fr-LU
Switzerland fr-CH
German Austria de-AT
Germany de-DE
Luxembourg de-LU
Switzerland de-CH
Greek Greece el-GR
Hungarian Hungary hu-HU
Italian Italy it-IT
Switzerland it-CH
Japanese Japan ja-JP
Korean South Korea ko-KR
Norwegian Bokmål Norway nb-NO
Polish Poland pl-PL
Portuguese Brazil pt-BR
Portugal pt-PT
Romanian Romania ro-RO
Russian Russian ru-RU
Slovak Slovakia sk-SK
Slovene Slovenia sl_SI
Spanish Argentina es-AR
Bolivia es-BO
Chile es-CL
Colombia es-CO
Costa Rica es-CR
Dominican Republic es-DO
Ecuador es-EC
El Salvador es-SV
Guatemala es-GT
Honduras es-HN
Mexico es-MX
Nicaragua es-NI
Panama es-PA
Paraguay es-PY
Peru es-PE
Puerto Rico es-PR
Spain es-ES
United States es-US
Uruguay es-UY
The LocalizationManager Functions 129
Language Locale Locale Name
Venezuela es-VE
Swedish Sweden sv-SE
Turkish Turkey tr-TR
The locale name consists of two parts: the language code and the country code, as
shown
<language code>_<COUNTRY CODE>
For example, to specify the Japanese locale, you would type:
jp_JP
If you need a more specific locale, you may add additional codes after the country
code. For example, to indicate French in France with a Euro dialect, you would
type:
fr_FR_EU
Function
Sub SetCurrentThreadLocale(
theLocale As String)
Parameters
Expression Type Description
theLocale String The name of the locale.
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following function checks the language string to determine which locale to use.
It then calls SetCurrentThreadLocale to set the appropriate locale.
Sub SetCurrentLanguage(Language)
Dim theManager ’ object
Set theManager = CreateObject("PureEdge.i18n_LocalizationManager")
If Language = "English" Then
theManager.SetCurrentThreadLocale "en_US"
Else
theManager.SetCurrentThreadLocale "fr_CA"
End If
End Sub
SetDefaultLocale
Description
This function sets the default locale the API uses when reporting errors, if no other
locale is specified. By default, the API uses the locale specified by the operating
system.
130
The API supports the following locales:
Language Locale Locale Name
Chinese Simplified Han, China zh-Hans-CN
Simplified Han, Singapore zh-Hans-SG
Traditional Han, Hong Kong S.A.R., China zh-Hant-HK
Traditional Han, Taiwan zh-Hant-TW
Croatian Croatia hr-HT
Czech Czech Republic cs-CZ
Danish Denmark da-DK
Dutch Belgium nl-BE
The Netherlands nl-NL
English Australia en-AU
Belgium en-BE
Canada en-Ca
Hong Kong S.A.R., China en-HK
India en-IN
Ireland en-IE
New Zealand en-NZ
Philippines en-PH
Singapore en-SG
South Africa en-ZA
United Kingdom en-GB
United States en-US
Finnish Finland fi-FI
French Belgium fr-BE
Canada fr-CA
France fr-FR
Luxembourg fr-LU
Switzerland fr-CH
German Austria de-AT
Germany de-DE
Luxembourg de-LU
Switzerland de-CH
Greek Greece el-GR
Hungarian Hungary hu-HU
Italian Italy it-IT
Switzerland it-CH
Japanese Japan ja-JP
Korean South Korea ko-KR
Norwegian Bokmål Norway nb-NO
Polish Poland pl-PL
Portuguese Brazil pt-BR
The LocalizationManager Functions 131
Language Locale Locale Name
Portugal pt-PT
Romanian Romania ro-RO
Russian Russian ru-RU
Slovak Slovakia sk-SK
Slovene Slovenia sl_SI
Spanish Argentina es-AR
Bolivia es-BO
Chile es-CL
Colombia es-CO
Costa Rica es-CR
Dominican Republic es-DO
Ecuador es-EC
El Salvador es-SV
Guatemala es-GT
Honduras es-HN
Mexico es-MX
Nicaragua es-NI
Panama es-PA
Paraguay es-PY
Peru es-PE
Puerto Rico es-PR
Spain es-ES
United States es-US
Uruguay es-UY
Venezuela es-VE
Swedish Sweden sv-SE
Turkish Turkey tr-TR
The locale name consists of two parts: the language code and the country code, as
shown
<language code>_<COUNTRY CODE>
For example, to specify the Japanese locale, you would type:
jp_JP
If you need a more specific locale, you may add additional codes after the country
code. For example, to indicate French in France with a Euro dialect, you would
type:
fr_FR_EU
Function
Sub SetDefaultLocale(
theLocale As String)
132
Parameters
Expression Type Description
theLocale String The name of the locale.
Returns
Returns nothing if the call is successful, or throws an exception if an error occurs.
Example
The following function checks the language string to determine which locale to use.
It then calls SetDefaultLocale to set the appropriate locale.
Sub SetDefaultLanguage(Language)
Dim theManager ’ object
Set theManager = CreateObject("PureEdge.i18n_LocalizationManager")
If Language = "English" Then
theManager.SetDefaultLocale "en_US"
Else
theManager.SetDefaultLocale "fr_CA"
End If
End Sub
The LocalizationManager Functions 133
134
The SecurityManager Functions
The SecurityManager functions allow you to retrieve the Security Manager and
obtain a hashing algorithm.
v To use the SecurityManager function you must import the IFS_COM_API type
library, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
v To use the SecurityManager function, you must first create the
PureEdge.security_SecurityManager object, as shown:
Set SecurityManager = _
CreateObject("PureEdge.security_SecurityManager")
You can then call the function on this object.
LookupHashAlgorithm
Description
This function retrieves a hash object. Use the hash object to hash shared secrets for
the ValidateHMACWithHashedSecret function.
Function
Function LookupHashAlgorithm(
algorithmName As String
) As IHash
Parameters
Expression Type Description
algorithmName String The name of the hash algorithm you want
to retrieve. The available hash algorithms
are sha1 and md5.
Returns
A hash object, or throws an exception if an error occurs.
Example
The following function validates an HMAC signature using a hashed secret. First,
the function uses DereferenceEx and GetLiteralByRefEx to locate the signature
item in a form. It then uses GetEngineCertificateList and GetDataByPath to locate
a server signing certificate. Next, it uses GetSignature and GetDataByPath to get
the signer’s common name and LookupHashAlgorith and Hash to create a hashed
secret. Finally, it uses ValidateHMACWithHashedSecret to determine if the
HMAC signature is valid, and returns ″Valid″ or ″Invalid″, as appropriate.
Note that this example also relies on a second function called StringToBinary. This
function converts a string to a single-byte binary array, which is required for the
hash function. This prevents COM from converting the string to a double-byte
array before hashing it, which would produce an incorrect result.
© Copyright IBM Corp. 2003, 2006 135
Function ValidateHMACSigHashed(Form)
Dim SigObject, XFDL, HashObject, SecurityManager ’ objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, HashedSecret, CommonName, _
SigItemRef ’ Strings
Dim Validation ’ Integer
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret
’ that is hashed, and sets SharedSecret to match. In most cases, this
’ would be a database lookup. For the purposes of this example, we will
’ use the Hash function to assign a hashed value to HashedSecret.
’ Get the Security Manager object
Set SecurityManager = _
CreateObject("PureEdge.security_SecurityManager")
’ Get the Hash object
Set HashObject = SecurityManager.LookupHashAlgorithm("sha1")
’ Set the Hashed secret. First convert the secret to a single-byte
’ binary array, then hash the secret.
136
SharedSecret = StringToBinary("secret")
HashedSecret = HashObject.Hash(SharedSecret)
’ Validate the signature
Validation = SigNode.ValidateHMACWithHashedSecret(HashedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSigHashed = "Valid"
Else
ValidateHMACSigHashed = "Invalid"
End If
End Function
’ The following function is required to convert a string to a single-byte ’
’ binary array before hashing that string. This prevents COM from converting
’ the string to a multi-byte format, which would produce an incorrect hash.
Function StringToBinary(String)
Dim Counter, Binary
For Counter = 1 to len(String)
Binary = Binary & ChrB(Asc(Mid(String, Counter, 1)))
Next
StringToBinary = Binary
End Function
The SecurityManager Functions 137
138
The Signature Functions
The Signature functions allow you to work with signature objects.
v To use the Initialization functions you must import the IFS_COM_API type
library, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
GetDataByPath
Description
This function retrieves a piece of data from a signature object.
Function
Function GetDataByPath(
thePath As String,
tagData As Boolean,
encoded As Boolean
) As String
Parameters
Expression Type Description
thePath String The path to the data you want to retrieve. See the
Notes section below for more information on data
paths.
tagData Boolean True if the path should be prepended to the data, or
False if not. If the path is prepended, an equals sign
(=) is used as a separator.
For example, suppose the path is ″Signing Cert:
Issuer: CN″ and the data is ″IBM″. If True, the path
will be prepended, producing ″CN=IBM″. If False,
the path will not be prepended, and the result will
be ″IBM″.
encoded Boolean True if the return data is base 64 encoded, or False
if not. The function returns binary data in base 64
encoding.
Notes
About Data Paths
Data paths describe the location of information within a signature, just like file
paths describe the location of files on a disk. You describe the path with a series of
colon separated tags. Each tag represents either a piece of data, or an object that
contains further pieces of data (just like directories can contain files and
subdirectories).
For example, to retrieve the version of a signature, you would use the following
data path:
© Copyright IBM Corp. 2003, 2006 139
Demographics
However, to retrieve the signer’s common name, you first need to locate the
signing certificate, then the subject, then finally the common name within the
subject, as follows:
SigningCert: Subject: CN
Some tags may contain more than one piece of information. For example, the
issuer’s organizational unit may contain a number of entries. You can either
retrieve all of the entries as a comma separated list, or you can specify a specific
entry by using a zero-indexed element number.
For example, the following path would retrieve a comma separated list:
SigningCert: Issuer: OU
Adding an element number of 0 would retrieve the first organizational unit in the
list, as shown:
SingingCert: Issuer: OU: 0
Signature Tags
The following table lists the tags available in a signature object. Note that
Clickwrap and HMAC Clickwrap signatures have additional tags (detailed in
Clickwrap Signature Tags and HMAC Clickwrap Tags).
Tag Description
Engine The security engine used to create the signature. This is an
object that contains further information, as detailed in
Security Engine Tags.
SigningCert The certificate used to create the signature. This is an object
that contains further information, as detailed in Certificate
Tags. Note that this object does not exist for Clickwrap or
HMAC Clickwrap signatures.
HashAlg The hash algorithm used to create the signature.
CreateDate The date on which the signature was created.
Demographics A string describing the signature.
LastVerificationStatus A short representing the verification status of the signature.
This is updated whenever the signature is verified. See
“VerifySignature” on page 107 for a complete list of the
possible values.
Clickwrap Signature Tags
The following table lists additional tags available in both Clickwrap and HMAC
Clickwrap signatures. Note that HMAC Clickwrap signatures have further tags
(detailed in HMAC Clickwrap Tags).
Tag Description
TitleText The text for the Windows title bar of the signature
dialog box.
MainPrompt The text for the title portion of the signature dialog box.
MainText The text for the text portion of the signature dialog box.
140
Tag Description
Question1Text The first question in the signature dialog box.
Answer1Text The signer’s answer.
Question2Text The second question in the signature dialog box.
Answer2Text The signer’s answer.
Question3Text The third question in the signature dialog box.
Answer3Text The signer’s answer.
Question4Text The fourth question in the signature dialog box.
Answer4Text The signer’s answer.
Question5Text The fifth question in the signature dialog box.
Answer5Text The signer’s answer.
EchoPrompt Text that the signer must echo to create a signature.
EchoText The signer’s response to the echo text.
ButtonPrompt The text that provides instructions for the Clickwrap
signature buttons.
AcceptText The text for the accept signature button.
RejectText The text for the reject signature button.
Certificate Tags
The following table lists the tags available in a certificate object. Note that
Clickwrap and HMAC Clickwrap signatures do not contain these tags.
Tag Description
Subject The subject’s distinguished name. This is an object that
contains further information, as detailed in
Distinguished Name Tags.
Issuer The issuer’s distinguished name. This is an object that
contains further information, as detailed in
Distinguished Name Tags.
IssuerCert The issuer’s certificate. This is an object that contains the
complete list of certificate tags.
Engine The security engine that generated the certificate. This is
an object that contains further information, as detailed
in Security Engine Tags.
Version The certificate version.
BeginDate The date on which the certificate became valid.
EndDate The date on which the certificate expires.
Serial The certificate’s serial number.
SignatureAlg The signature algorithm used to sign the certificate.
PublicKey The certificate’s public key.
FriendlyName The certificate’s friendly name.
Distinguished Name Tags
The Signature Functions 141
The following table lists the tags available in a distinguished name object. Note
that Clickwrap and HMAC Clickwrap signatures do not contain these tags.
Tag Description
CN The common name.
E The e-mail address.
T The title.
O The organization.
OU The organizational unit.
C The country.
L The locality.
ST The state.
All The entire distinguished name.
HMAC Clickwrap Tags
The following table lists the tags available in HMAC Clickwrap signature. Note
that these tags are in addition to both the regular Signature Tags and the
Clickwrap Signature Tags.
Tag Description
HMACSigner A string indicating which answers store the signer’s ID.
HMACSecret A string indicating which answers store the signer’s
secret.
Notarization The notarizing signatures. This is one or more signature
objects that contain further information, as detailed in
Signature Tags . There can be any number of notarizing
signatures. Use an element number to retrieve a specific
signature. For example, to get the first notarizing
signature use:
Notarization: 0
If no element number is provided, the data will be
retrieved from the first valid notarizing signature found.
If no valid notarizing signatures are found, the function
will return null.
Security Engine Tags
The following table lists the tags available in the security engine object:
Tag Description
Name The name of the security engine used by the server.
Help The help text for the security engine.
HashAlg A hash algorithm supported by the security engine.
Returns
A string containing the certificate data (null if no data is found), or throws an
exception if an error occurs.
142
Example
The following function uses DereferenceEx and GetLiteralByRefEx to locate the
signature item in a form. It then uses GetEngineCertificateList and
GetDataByPath to locate a server signing certificate. Next, it uses GetSignature
and GetDataByPath to get the signer’s common name. Finally, it uses
ValidateHMACWithSecret to determine if the HMAC signature is valid, and
returns ″Valid″ or ″Invalid″, as appropriate.
Function ValidateHMACSig(Form)
Dim SigObject, XFDL ’ Objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, CommonName, SigItemRef ’ Strings
Dim Validation ’ Integer
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret,
’ and sets SharedSecret to match. In most cases, this would be a
’ database lookup. For the purposes of this example, we will simply
’ assign a value to SharedSecret.
The Signature Functions 143
SharedSecret = "secret"
’ Validate the signature
Validation = SigNode.ValidateHMACWithSecret(SharedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSig = "Valid"
Else
ValidateHMACSig = "Invalid"
End If
End Function
GetSigningCert
Description
This function retrieves the signing certificate from a signature object.
Function
Function GetSigningCert() As Certificate
Parameters
There are no parameters for this function.
Returns
The signing certificate.
Example
The following example gets the signing certificate from a signature object, then
iterates through the certificate issuers until it reaches the end of the chain. During
the iteration, each certificate is passed to a function that processes them.
Sub processCertChain(TheSig)
Dim TheCert, IssuerCert ’ Variant
’ Get the signing certificate from the signature
Set TheCert = TheSig.GetSigningCert
’ Loop through the certificate chain, passing each certificate to the
’ ProcessCert function. The loop ends when the issuer certificate is
’ Nothing.
Do While (Not(TheCert Is Nothing))
’ Pass the certificate to the ProcessCert function. Note that
’ this is not an API function, but rather a function you would
’ write to process the certificate in some way.
ProcessCert(TheCert)
’ Get the issuer certificate from the TheCert
Set IssuerCert = TheCert.GetIssuer(1) ’ vbNull
144
’ Assign theCert to equal the issuerCert for next iteration of the
’ loop.
Set TheCert = IssuerCert
Loop
End Sub
The Signature Functions 145
146
The XFDL Functions
The XFDL functions create the root nodes of forms and handle administrative tasks
related to the Form Library.
v To use the Initialization functions you must import the IFS_COM_API type
library, as shown:
<!-- METADATA TYPE = "typelib"
FILE = "c:\winnt\system32\IFS_COM_API.tlb" -->
v To use the XFDL functions, you must first create the PureEdge.xfdl_XFDL object,
as shown:
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
You can then call the function on this object.
Create
Description
This function creates a new IFormNodeP and attaches it to the form hierarchy at
the indicated location. Once created, the type and identifier of a IFormNodeP
cannot be changed.
Note that you can also use SetLiteralByRefEx to create an IFormNodeP at the
option level and below. Using SetLiteralByRefEx is often easier and faster than
using Create.
Function
Function Create(
aNode As IFormNodeP,
where As Long,
theType As String,
theLiteral As String,
theFormula As String,
theIdentifier As String
) As IFormNodeP
Parameters
Expression Type Description
aNode IFormNodeP The new IFormNodeP is placed in the form hierarchy
in relation to this node. If null, this creates a new
IFormNodeP hierarchy (a new form)
© Copyright IBM Corp. 2003, 2006 147
Expression Type Description
where Long A constant that describes the location, in relation to the
parameter aNode, in which the new node should be
placed:
UFL_APPEND_CHILD — adds the new node as the
last child of aNode.
UFL_AFTER_SIBLING — adds the new node as a
sibling of aNode, placing it immediately after that node.
UFL_BEFORE_SIBLING — adds the new node as a
sibling of aNode, placing it immediately before that
node.
Note: If the parameter aNode is null, then this
parameter should be set to 0.
theType String The type to assign to the IFormNodeP being created.
This is only necessary for page and item nodes. Use
null for all other nodes. The type cannot be changed
after the node has been created.
If you are creating a non-XFDL node, you must also
include the namespace that the node should belong to,
as shown:
<namespace prefix>:<type>
For example:
custom:myItem
If you do not provide a namespace, the function will
assign the default namespace for the form.
theLiteral String The literal to assign to this IFormNodeP. null is valid.
theFormula String The formula to assign to this IFormNodeP. null is
valid.
theIdentifier String The identifier to assign to this IFormNodeP. The
identifier cannot be changed after the node has been
created. null is valid.
If you are creating an option or argument level node,
this must also include the namespace the node should
belong to. Use the following format:
<namespace prefix>:<type>
For example:
custom:myOption
If you do not provide a namespace, the function will
assign the default namespace for the form.
Returns
The new IFormNodeP or throws an exception if an error occurs.
148
Example
The following example adds a label to a form. A node is passed into the function,
which then uses GetLiteralByRefEx to read the value of a field. The function then
uses DereferenceEx to locate the field node, and creates a label node as a sibling
using Create. Finally, the function creates a value for the new label node using
SetLiteralByRef.
Sub AddLabel(Form)
Dim TempNode, XFDL ’ objects
Dim Name ’ strings
Set TempNode = Form
’ Get the value of the NameField.value option node
Name = TempNode.GetLiteralByRefEx(vbNullString, _
"PAGE1.NameField.value", 0, vbNullString, Nothing)
’ Locate the NameField item node in the first page of the form
Set TempNode = TempNode.DereferenceEx(vbNullString, _
"PAGE1.NameField", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get an XFDL object
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Create a label. This label is created as a sibling of the NameField,
’ and is named NameLabel.
Set TempNode = XFDL.Create(TempNode, UFL_AFTER_SIBLING, "label", _
vbNullString, vbNullString, "NameLabel")
’ Create a value option for the label. This option is assigned the
’ value of Name (as read from the field)
TempNode.SetLiteralByRefEx vbNullString, "value", 0, vbNullString, _
Nothing, Name
End Sub
GetEngineCertificateList
Description
This function locates all available certificates for a particular signing engine.
Function
Function GetEngineCertificateList(
engineName As String,
theStatus As Long
) As CertificateList
Parameters
Expression Type Description
engineName String The name of the signing engine. Valid signing
engines include: Generic RSA, CryptoAPI,
Netscape, and Entrust. (Note that Generic RSA
is the union of CryptoAPI and Netscape.)
The XFDL Functions 149
Expression Type Description
theStatus Long This is a status flag that reports whether the
operation was successful. Possible values are:
SUSTATUS_OK — the operation was
successful.
SUSTATUS_CANCELLED — the operation
was cancelled by the user.
SUSTATUS_INPUT_REQUIRED — the
operation required user input, but could not
receive it (for example, it was run on a server
with no user).
Returns
A collection containing the list of certificates objects.
Example
The following function uses DereferenceEx and GetLiteralByRefEx to locate the
signature item in a form. It then uses GetEngineCertificateList and
GetDataByPath to locate a server signing certificate. Next, it uses GetSignature
and GetDataByPath to get the signer’s common name. Finally, it uses
ValidateHMACWithSecret to determine if the HMAC signature is valid, and
returns “Valid” or “Invalid”, as appropriate.
Function ValidateHMACSig(Form)
Dim SigObject, XFDL ’ Objects
Dim TheCerts ’ CertificateList
Dim Cert, SigningCert ’ ICertificate
Dim SignerName, SharedSecret, CommonName, SigItemRef ’ Strings
Dim Validation ’ Integer
Dim TempNode, SigNode ’ IFormNodeP
Set TempNode = Form
’ Get the SignatureButton node
Set TempNode = Form.DereferenceEx(vbNullString, _
"PAGE1.HMACSignatureButton", 0, UFL_ITEM_REFERENCE, Nothing)
’ Get the name of the signature item
SigItemRef = TempNode.GetLiteralByRefEx(vbNullString, "signature", _
0, vbNullString, Nothing)
’ Get the signature item node
Set SigNode = TempNode.DereferenceEx(vbNullString, SigItemRef, 0, _
UFL_ITEM_REFERENCE, Nothing)
’ Get available server certificates for Generic RSA signing
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TheCerts = XFDL.GetEngineCertificateList("Generic RSA", 1)
’ vbNull
’ Locate the certificate that has a common name of "User1-CP.02.01".
’ This is the certificate we will use when verifying the signature.
150
For Each Cert in TheCerts
CommonName = Cert.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
If CommonName = "User1-CP.02.01" Then
Set SigningCert = Cert
End If
Next
’ Get the signature object from the signature node
Set SigObject = SigNode.GetSignature
’ Get the signer’s name from the signature object
SignerName = SigObject.GetDataByPath("SigningCert: Subject: CN", _
False, 1) ’ vbNull
’ Include code that matches the signer’s identity to a shared secret,
’ and sets SharedSecret to match. In most cases, this would be a
’ database lookup. For the purposes of this example, we will simply
’ assign a value to SharedSecret.
SharedSecret = "secret"
’ Validate the signature
Validation = SigNode.ValidateHMACWithSecret(SharedSecret, _
SigningCert, 1) ’ vbNull
’ Check the validation code and return either "Valid" or "Invalid"
If Validation = UFL_DS_OK Then
ValidateHMACSig = "Valid"
Else
ValidateHMACSig = "Invalid"
End If
End Function
IsDigitalSignaturesAvailable
Description
This function determines whether digital signatures are available on the current
computer.
Function
Function IsDigitalSignaturesAvailable() As Boolean
Parameters
There are no parameters for this function.
Returns
True if digital signatures are available on this computer; otherwise, False. On error,
the function throws an exception.
The XFDL Functions 151
Example
The following function calls IsDigitalSignaturesAvailable to deterimine whether
the digital signature engine is available. If so, it returns ″Available″; otherwise, it
returns ″Not Available″.
Function SigsAvailable()
Dim XFDLObject ’ Object
Dim Available ’ Boolean
’ Get the XFDL object.
Set XFDLObject = CreateObject("PureEdge.xfdl_XFDL")
’ Check to see if the engine is available.
Available = XFDLObject.IsDigitalSignaturesAvailable
’ Return the appropriate response.
If Available = True Then
SigsAvailable = "Available"
Else
SigsAvailable = "Not Available"
End If
End Function
ReadForm
Description
This function will read a form into memory from a specified file .
Function
Function ReadForm(
theFilePath As String,
flags As Long
) As IFormNodeP
Parameters
Expression Type Description
theFilePath String The path to the source file on the local disk.
152
Expression Type Description
flags Long The following flags cause special behaviors. If
using multiple flags, combine them using a
bitwise OR. For example:
UFL_AUTOCOMPUTE_OFF |
UFL_AUTOCREATE_FORMATS_OFF
0 — no special behavior.
UFL_AUTOCOMPUTE_OFF — Reads the form
into memory, but disables the compute system so
that no computes are evaluated.
UFL_AUTOCREATE_CONTROLLED_OFF —
Reads the form into memory, but disables the
creation of all options that are maintained only in
memory (for example, itemnext, itemprevious,
pagenext, pageprevious, and so on).
UFL_AUTOCREATE_FORMATS_OFF — Reads
the form into memory, but disables the evaluation
of all format options.
UFL_SERVER_SPEED_FLAGS — Turns off the
following features: computes, automatic
formatting, duplicate sid detection, the event
model, and relative page and item tags (for
example, itemprevious, itemnext, and so on). This
setting significantly improves server processing
times.
UFL_XFORMS_INITIALIZE_ONLY — Turns off
the following features: controlled item
construction, UI connection to the XForms model,
action handling set up, and the
rebuild/recalculate/revalidate/refresh sequence
after instance replacements.
Returns
Returns an IFormNodeP that is the root node of the form, or throws an exception
if an error occurs.
Notes
Duplicate Scope IDs
If a form contains duplicate scope IDs (for example, two items on the same page
with the same SID), ReadForm will fail to read the form and will return an error.
This enforces correct XFDL syntax, and eliminates certain security risks that exist
when duplicate scope IDs appear in signed forms.
Digital Signatures
When a form containing one or more digital signatures is read, the signatures will
be verified. The result of the verification is stored in a flag that can be checked by
calling GetSignatureVerificationStatus.
The XFDL Functions 153
Note that this flag is only set by ReadForm, and its value will not be adjusted by
changes made to the form after it has been read. This means that calls such as
SetLiteralEx may actually break a signature (by changing the value of a signed
item), but that this will not adjust the flags value. To verify a signature after
changes have been made to a form, it is best to use VerifyAllSignatures.
Note that when a form is signed, all signed computes are frozen at their start value
(regardless of whether the compute system is disabled).
Server-Side Processing
Using the UFL_SERVER_SPEED_FLAGS setting significantly improves
performance during server-side processing. We strongly recommend you use this
flag if you do not require computes to update while processing the form.
Example
In the following example, the function uses ReadForm to load a form into memory
and return the root node of the form.
Function LoadForm(FileName)
Dim DTK, XFDL, TempForm ’ objects
’ Get a DTK object and initialize the API
Set DTK = CreateObject("PureEdge.DTK")
DTK.IFSInitialize "aspApp", "1.0.0", "6.5.0"
’ Get an XFDL object and read the form from the supplied file
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
Set TempForm = XFDL.ReadForm(FileName, 0)
’ Return the form
Set LoadForm = TempForm
End Function
ReadFormFromASPRequest
Description
This function will read a form into memory from the ASP request object.
Function
Function ReadFormFromASPRequest(
flags As Long
) As IFormNodeP
154
Parameters
Expression Type Description
flags Long The following flags cause special behaviors. If using
multiple flags, combine them using a bitwise OR.
For example:
UFL_AUTOCOMPUTE_OFF |
UFL_AUTOCREATE_FORMATS_OFF
0 — no special behavior.
UFL_AUTOCOMPUTE_OFF — Reads the form into
memory, but disables the compute system so that no
computes are evaluated.
UFL_AUTOCREATE_CONTROLLED_OFF —
Reads the form into memory, but disables the
creation of all options that are maintained only in
memory (for example, itemnext, itemprevious,
pagenext, pageprevious, and so on).
UFL_AUTOCREATE_FORMATS_OFF — Reads the
form into memory, but disables the evaluation of all
format options.
UFL_SERVER_SPEED_FLAGS — Turns off the
following features: computes, automatic formatting,
duplicate sid detection, the event model, and
relative page and item tags (for example,
itemprevious, itemnext, and so on). This is intended
to decrease server processing times.
UFL_XFORMS_INITIALIZE_ONLY — Turns off the
following features: controlled item construction, UI
connection to the XForms model, action handling set
up, and the rebuild/recalculate/revalidate/refresh
sequence after instance replacements.
Returns
Returns an IFormNodeP that is the root node of the form, or throws an exception
if an error occurs.
Notes
Duplicate Scope IDs
If a form contains duplicate scope IDs (for example, two items on the same page
with the same SID), ReadForm will fail to read the form and will return an error.
This enforces correct XFDL syntax, and eliminates certain security risks that exist
when duplicate scope IDs appear in signed forms.
Digital Signatures
When a form containing one or more digital signatures is read, the signatures will
be verified. The result of the verification is stored in a flag that can be checked by
calling GetSignatureVerificationStatus.
The XFDL Functions 155
Note that this flag is only set by ReadForm, and its value will not be adjusted by
changes made to the form after it has been read. This means that calls such as
SetLiteralEx may actually break a signature (by changing the value of a signed
item), but that this will not adjust the flag’’s value. To verify a signature after
changes have been made to a form, it is best to use VerifyAllSignatures.
Note that when a form is signed, all signed computes are frozen at their start value
(regardless of whether the compute system is disabled).
Example
The following example uses ReadFormFromASPRequest to load a form into
memory and return the root node of the form.
Function LoadFormFromRequestObject()
Dim DTK, XFDL, TempForm ’ objects
’ Get a DTK object and initialize the API
Set DTK = CreateObject("PureEdge.DTK")
DTK.IFSInitialize "aspApp", "1.0.0", "6.5.0"
’ Get an XFDL object and read the form from the request object
Set XFDL = CreateObject("PureEdge.xfdl_XFDL")
’ Read the form into memory
Set TempForm = XFDL.ReadFormFromASPRequest(0)
’ Return the form
Set LoadFormFromRequestObject = TempForm
End Function
156
Appendix. Notices
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operation of any non-IBM product, program, or service.
IBM may have patents or pending patent applications covering subject matter
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Licensing
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PUBLICATION “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER
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© Copyright IBM Corp. 2003, 2006 157
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Trademarks
The following terms are trademarks of International Business Machines
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in the United States, other countries, or both.
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United States, other countries, or both.
Other company, product, or service names may be trademarks or service marks of
others.
158
Index
Special characters
-> symbol 7
A
about
the API 3
AddNamespace function 35
algorithm, looking up a hash algorithm 135
API
about the API 3
differences between Java, C, and COM 3
list of Form Library functions 23
where the API fits into your system 3
applications
compiling your application, tutorial 20
testing your application, tutorial 20
argument nodes 5, 9
ASP
reading a form from the ASP request object 154
writing a form to the ASP response object 110
attachments
attaching files to a form 46
extracting attachments from a form 48
removing an attachment 86
attributes
getting the value of an attribute 52
removing an attribute 85
setting an attribute 89
Authenticated Clickwrap
validating Authenticated Clickwrap signatures 99, 102
C
C API, differences from Java and COM 3
cell item
locating a cell in a particular group 40
cells, creating 37
Certificate functions 29
certificates
getting a Blob of the certificate 29
getting a list of available certificates 54, 149
getting specific certificate data 30
getting the issuer certificate 33
getting the signing certificate from a signature 144
CheckValidFormats function 37
child nodes, locating 55
closing a form 44
tutorial 20
COM API, differences from C and Java 3
compiling
compiling your application, tutorial 20
computations. See computes 1
compute node property 5
computes
deactivating the compute system 88, 155
setting a compute 91
constants 4
FormNodeP constants 35
constants (continued)
See also formNodeP constants[constants
a] 1
See also Function Call constants[constants
a] 1
conventions for functions descriptions 26
conventions, document 1
copying a node 45
Create function 147
CreateCell function 37
creating
a form or node 147
creating cells in a form 37
creating forms 42
creating nodes 42
current value
about signed computes 26
D
data
retrieving a value from a form, tutorial 17
setting a value in a form, tutorial 18
data item
locating a particular data item in a datagroup 40
data model, updating the XML data model 111
datagroup
locating a particular data item in a datagroup 40
DeleteSignature function 38
deleting
a form 20
deleting a form from memory 44
removing an enclosure from a form 86
DereferenceEx function 40
dereferencing 7
special notes on 93
Designer 3
designing XFDL forms 3
Destroy function 44
destroy method
tutorial 20
digital certificates, getting a list of available cetificates 54, 149
digital certificates. See certificates 1
digital signatures
determining if signatures are available 151
digital signatures. See signatures 1
distributing applications tutorial 21
document conventions 1
Duplicate function 45
duplicating a node 45
E
EncloseFile function 46
EncloseInstance function 47
enclosures
enclosing files in a form 46
extracting enclosures from a form 48
removing an enclosure 86
error message, getting the language for 123, 125
© Copyright IBM Corp. 2003, 2006 159
error message, setting the language for 128, 130
errors, reporting errors 26
Extensible Forms Description Language. See XFDL 1
ExtractFile function 48
extracting enclosures 48
ExtractInstance function 49
ExtractXFormsInstance function 51
F
form
determining the version of a form 56
Form Library
getting started 13, 15
initializing the Form Library 16, 117
list of Form Library functions 23
See also functions[Form Library
a] 1
form nodes 5, 9
form. See forms 1
formatting
determining whether a node is correctly formatted 83
determining whether all the nodes in a form ares correctly
formatted 37
formNodeP
creating a formNodeP 42
formNodeP structure 5
FormNodeP
See also nodes[formNodeP
a] 1
formNodeP constants
UFL_AFTER_SIBLING 45
UFL_APPEND_CHILD 45, 148
UFL_BEFORE_SIBLING 45, 148
UFL_ORPHAN 45
FormNodeP constants 35
forms
writing a form to disk 109, 110
formula node property 5
formulas
about signed formulas 26
setting a formula 91
freeing memory 44
tutorial 20
function calls. See functions 1
functions 54
about the function descriptions 26
AddNamespace 35
Certificate functions 29
CheckValidFormats 37
Create 147
CreateCell 37
DeleteSignature 38
DereferenceEx 40
Destroy 44
Duplicate 45
EncloseFile 46
EncloseInstance 47
ExtractFile 48
ExtractInstance 49
ExtractXFormsInstance 51
GetAttribute 52
GetBlob 29
getChildren 55
GetDataByPath 30, 139
GetDefaultLocale 123, 125
GetEngineCertificateList 149
functions (continued)
GetFormVersion 56
GetIdentifier 57
GetIssuer 33
GetLiteralByRefEx 58
GetLiteralEx 61
GetLocalName 62
GetNamespaceURI 63
GetNamespaceURIFromPrefix 64
GetNext 66
GetNodeType 67
getParent 68
GetPrefix 69
GetPrefixFromNamespaceURI 71
GetPrevious 72
GetReferenceEx 73
GetSecurityEngineName 77
getSigLockCount 78
GetSignature 78
GetSignatureVerificationStatus 80
GetSigningCert 144
GetType 81
Hash 113
Hash functions 113
IFormNodeP functions 35
IFSInitialize 117
IFSInitializeWithLocale 119
IsDigitalSignaturesAvailable 151
IsSigned 82
IsValidFormat 83
IsXFDL 84
list of Form Library functions 23
LocalizationManager functions 123
LookupHashAlgorithm 135
ReadForm 152
ReadFormFromASPRequest 154
Remove Enclosure 86
RemoveAttribute 85
ReplaceXFormsInstance 87
SecurityManager functions 135
See also string functions[functions
a] 1
SetActiveForComputationalSystem 88
SetAttribute 89
SetCurrentThreadLocale 128
SetDefaultLocale 130
SetFormula 91
SetLiteralByRefEx 92
SetLiteralEx 95
Signature functions 139
SignForm 96
UpdateXFormsInstance 97
ValidateHMACWithHashedSecret 102
ValidateHMACWithSecret 99
VerifyAllSignatures 106
VerifySignature 107
WriteForm 109
WriteFormToASPResponse 110
XFDL functions 147
XMLModelUpdate 111
G
GetAttribute function 52
GetBlob function 29
GetCertificateList 54
GetCertificateList function 54
160
getChildren function 55
GetCurrentThreadLocale function 123
GetDataByPath function 30, 139
GetDefaultLocale function 125
GetEngineCertificateList function 149
GetFormVersion function 56
GetIdentifier function 57
GetIssuer function 33
GetLiteralByRefEx function 58
GetLiteralEx function 61
GetLocalName function 62
GetNamespaceURI function 63
GetNamespaceURIFromPrefix function 64
GetNext function 66
GetNodeType function 67
getParent function 68
GetPrefix function 69
GetPrefixFromNamespaceURI function 71
GetPrevious function 72
GetRererenceEx function 73
GetSecurityEngineName function 77
GetSigLockCount function 78
GetSignature function 78
GetSignatureVerificationStatus function 80
GetSigningCert function 144
getting started
with the Form Library 15
getting started with the Form Library 13
GetType function 81
global
item 9
page node 9
group
locating a cell in a particular group 40
H
hash algorithm, looking up an algorithm 135
Hash function 113
Hash functions 113
hashes
creating a hash 113
hierarchy
about the node hierarchy 5
HMAC signatures
validating HMAC signatures 99, 102
validating Signature Pad signatures 99, 102
I
identifier node property 5
IFormNodeP
IFormNodeP functions 35
IFormNodeP constants
UFL_NEXT 41
UFL_SAVE_ALLOW 110, 111
UFL_TRANSMIT_ALLOW 111
IFormNodeP objects
about 4
creating an IFormNodeP object 147
freeing IFormNodeP objects from memory 4
IFSinitialize function 117
IFSinitializeWithLocale function 119
ifx files. See extensions 1
initializing
initializing the API 117
initializing (continued)
initializing the API with locale 119
initializing the Form Library 16, 117
instances, XForms
adding to an instance 97
extracting an instance 51
replacing an instance 87, 97
updating an instance 97
instances, XML
enclosing an instance 47
extracting an instance 49
Interlink signatures
validating 99, 102
IsDigitalSignaturesAvailable function 151
IsSigned function 82
IsValidFormat function 83
IsXFDL function 84
item node 5, 9
item, global 9
J
Java API, differences from C and COM 3
L
language, getting the current language 123
language, getting the default language 125
language, setting the current language 128
language, setting the default language 130
literal property
about 5
getting the value of 58, 61
setting the value 92
setting the value of the literal property 95
loading a form
tutorial 17
loading forms
loading forms into memory 152, 154
local names
getting the local name of a node 62
locale
initializing the API with locale 119
locale, getting the current locale 123
locale, getting the default locale 125
locale, setting the current locale 128
locale, setting the default locale 130
LocalizationManager functions 123
locating a node 40
lock count, getting for a node 78
LookupHashAlgorithm function 135
M
memory, freeing 20, 44
memory, freeing IFormNodeP objects 4
N
names, getting the security engine name 77
namespace
adding a namespace to a form 35
determining if a node is in the XFDL namespace 84
getting the local name of a node 62
getting the namespace prefix for a namespace URI 71
Index 161
namespace (continued)
getting the namespace prefix for a node 69
getting the namespace URI for a node 63
getting the namespace URI from a prefix 64
null namespace 8
using namespace in references 8
node properties
compute property 5
formula property 5
identifier property 5
literal property 5
table of properties 10
type 5
node structure
advanced information 8
tree structure 9
nodes
about the node hierarchy 5
adding as child 45, 148
adding as new form 45
adding as sibling 45, 148
argument 9
argument nodes 5
compute property 5
creating form nodes 147
creating nodes 42
determining how many times a node has been signed 78
duplicating a node 45
form nodes 5, 9
forumula property 5
getting the literal value 58
getting the literal value of a node 61
getting the type of a node 57, 81
global page nodes 9
identifier property 5
item 9
item nodes 5
literal property 5
locating a child node 55
locating a node 40
locating the parent node 68
node properties 10
node tree structure 9
option 9
option nodes 5
page 5
page nodes 9
reference, getting for a particular node 73
root nodes 9
See also attributes 52
See also local names 62
See also namespace 62
setting the literal value 92
setting the literal value of a node 95
setting the value of signed nodes 95
table of node properties 10
traversing nodes 66, 72
type property 5
type, determining the node type 67
O
objects
getting a signature object 78
Hash objects 113, 135
IFormNodeP objects 4
option nodes 5, 9
output paramaters, limitations 27
P
page node 5, 9
global page node 9
parameters, limitations to output parameters 27
parent nodes, traversing parent nodes 68
prefix, namespace See namespace 64
properties
table of node properties 10
R
ReadForm function 152
setting the current value of items 26
ReadFormFromASPRequest function 154
reading
reading forms into memory 152, 154
references
getting a reference to a particular node 73
syntax of a reference 6
using namespace in references 8
using the null namespace in references 8
RemoveAttribute function 85
RemoveEnclosure function 86
removing
removing a form from memory 44
removing enclosures 86
ReplaceXFormsInstance function 87
request object, reading a from from the ASP request
object 154
response object, writing a form to the ASP response
object 110
root nodes 9
S
saving a form to disk 109, 110
tutorial 19
saving enclosures to disk 48
secret, hashing a secret 113
security engines, getting the name 77
SecurityManager functions 135
SetActiveForComputationalSystem function 88
SetAttribute function 89
SetCurrentThreadtLocale function 128
SetDefaultLocale function 130
SetFormula function 91
SetLiteralByRefEx function 92
SetLiteralEx function 95
shared secret, hashing a shared secret 113
Signature functions 139
Signature Pad signatures, validating
signatures
validtating Signature Pad signatures 99, 102
signatures
creating signatures 96
deleting signatures 38
destroying signatures 44
determining how many times a node has been signed 78
determining if a signature is valid 80
determining whether a node is signed 82
getting a signature object 78
getting specific signature data 139
getting the signing certificate from a signature 144
162
signatures (continued)
setting the value of nodes that are already signed 95
validating HMAC signatures 99, 102
validating Interlink signatures 99, 102
validating Topaz signatures 99, 102
validating WinTab signatures 99, 102
verifying 107
verifying signatures 106
SignForm function 96
signing
signing a formula 26
strings
hashing a string 113
structures
formNodeP structure 5
system, where the API fits 3
T
Topaz signatures, validating 99, 102
traversing nodes 55, 66, 72
traversing child nodes to particular count 55
traversing parent nodes 68
tree structure
sample 9
XFDL 8
tutorials
closing a form 20
compiling your application 20
distributing applications 21
freeing memory 20
getting started
with the Form Library 13
loading a form 17
retrieving a value from a form 17
setting a value in a form 18
testing your application 20
writing a form to disk 19
type
determining the node type 67
node property 5
U
UFL_AFTER_SIBLING constant 45
UFL_APPEND_CHILD constant 45, 148
UFL_BEFORE_SIBLING constant 45, 148
UFL_NEXT constant 41
UFL_ORPHAN constant 45
UFL_SAVE_ALLOW constant 110, 111
UFL_TRANSMIT_ALLOW constant 111
UpdateXFormsInstance function 97
updating the XForms data model 51, 87, 97
V
ValidateHMACWithHashedSecret function 102
ValidateHMACWithSecret function 99
validating signatures 80
values, setting a value in a form, tutorial 18
VerifyAllSignatures function 106
verifying signatures 106, 107
VerifySignature function 107
version
determining the version of a form 56
Viewer 3
viewing XFDL forms 3
W
WinTab signatures, validating 99, 102
Workplace Forms Designer 3
Workplace Forms Viewer 3
WriteForm function 109
writeForm method
tutorial 19
WriteFormToASPResponse function 110
writing a form to disk 109, 110
tutorial 19
X
XFDL functions 147
XFDL tree structure 8
XFDL, about 1
XForms data model, updating 51, 87, 97
XForms instances
adding to an instance 97
extracting an instance 51
replacing an instance 87, 97
updating an instance 97
XForms Model update 51, 87, 97
XML data model, updating 111
XML instances
enclosing an instance 47
extracting an instance 49
XMLModelUpdate function 111
Index 163
164
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Program Number: 5724-N08
Printed in USA
S229-1528-00

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