XML Unleashed

XFA and DTDs

Considering that XFA scripts use an extended XML syntax, you might be wondering how DTDs fit into the XFA equation. Aside from defining its own extended syntax, XFA also includes its own DTD syntax. The term "DTD syntax" is somewhat misleading because this is more similar to XML Schema than to traditional XML DTDs. Like XML Schema, XFA's DTD syntax relies on familiar XML syntax to describe the structure of documents. In other words, you use elements and attributes to describe the structure of a document, instead of the cryptic codes used in traditional DTDs. Documents created using XFA's DTD syntax are also known as XFA schemas.

To help you make the transition from traditional DTDs to XFA schemas, XFA provides a special function ...