XFDL Specification

The XFDL Specification describes a class of XML documents called Extensible Forms Description Language (XFDL) forms and partially describes the behavior of computer programs that process them. An XFDL processor is a software program that reads, processes, and writes XFDL forms. Processing may include such tasks as GUI rendering, data extraction, or modification.

What's new in XFDL 8.0
This version of XFDL includes several new features and improvements that allow form designers to create visually compelling interfaces for their clients.
Origin and goals
XFDL is a powerful, complex forms definition syntax that promotes application interoperability and adherence to worldwide Internet standards.
References
Terminology
Notation
XFDL forms are XML documents; the form definition is encoded using XML elements and attributes.
Overlap with other specifications
To serve its purpose, XFDL requires comprehensive presentation control and data typing machinery.
Non-repudiation and the document-centric model
Form names and extensions
To ensure cross-platform compatibility, form names should avoid the use of characters that are illegal under popular operating systems or in URLs. Form names should also include the .xfdl extension. The extension .xfd can also be used, but it should be avoided if possible.
MIME types
Structure of XFDL forms
This section describes the general structure of XFDL forms.
About signing forms
To properly implement support for digital signatures in an XFDL document, you should consider common use scenarios and overall security.
XFDL form example
Global settings
Global settings specify default settings that can be applied to an entire form or a page.
Items
Items are the basic elements of a page. Each item on the page must have a unique scope identifier (sid.) You can also add custom items to your forms.
Options
In the XFDL language, options define the characteristics given to a form, a page, or an item. XForms options link the XFDL items on the form to the XForms data model, so that the items and model share data.
XForms actions
XForms actions are similar to the XFDL actions you can create using the action item. XForms actions allow you to initiate a number of processes, including submitting a form, setting a value in a form, inserting a row in a repeat table, and so on.
XForms event handlers
XForms event handlers track events in the form, such as a button click or the selection of a particular choice. When these events occur, they are registered by the XForms system. This allows you to create actions that are triggered by these events.
Function calls
Function calls allow form designers to create complex computations and calculations in their forms.
Signature basics
Signatures are applied to forms as a security measure for both the provider and the user of the form. This topic contains introductory information and descriptions of the fields used to create signature buttons.
XFDL compute system
An XFDL compute is an expression that controls the character content of an element at or under the element depth of an XFDL option.
Reference
The XFDL reference section includes easy to use reference and cross reference tables, information on the default sizes of items, the order of precedence for signature and transmission filters, as well as detailed locale information.
Locale information
IBM® Forms are designed to be locale and language aware. This means that each form is designed for a specific language and locale.
Notices