When XML is used as the basis for a transaction between two parties, the ability to know whether a document is properly formed is important when working across organizational boundaries where contractual obligations are used to define the responsibilities of each party. In this chapter, we work with structured XML formats, convert non-XML information to structured XML, and validate XML documents against their DTDs. We examine aspects of working with official XML dialects, the impact the process of validation can have on your system design, and explore ebXML (Electronic Business XML) at a high level.

Let’s first look at the base technologies: Document Type Definitions (DTDs; discussed in Chapter 2), validating parsers, and web forms. These technologies make exchanging XML documents reliable and flexible. Afterwards, we’ll dive into some in-depth examples that touch on different aspects of working with validation.