This chapter demonstrated an alternative approach to the event-based method of parsing XML data. The Document Object Model (DOM) builds a representation of the document structure in memory, and provides the application layer with a standard API to traverse and manipulate this tree.
PHP implements the DOM via a number of standard classes; this chapter examined these classes in detail, together with examples of how they can be used to format XML data, construct XML documents on the fly, and create customized representations of XML data.
Finally, the concluding section of this chapter examined the pros and cons of the SAX and DOM approaches, discussing them vis-a-vis with each other, in an attempt to help developers with the correct approach for their specific requirements.
In the next chapter, I will be discussing Extensible Stylesheet Language Transformations (XSLT), which provides developers with yet another option when it comes to formatting and processing XML data.