Chapter 12

DOM Levels 2 and 3


  • Changes to the DOM introduced in Levels 2 and 3
  • The DOM API for manipulating styles
  • Working with DOM traversal and ranges

The first level of the DOM focuses on defining the underlying structure of HTML and XML documents. DOM Levels 2 and 3 build on this structure to introduce more interactivity and support for more advanced XML features. As a result, DOM Levels 2 and 3 actually consist of several modules that, although related, describe very specific subsets of the DOM. These modules are as follows:

  • DOM Core — Builds on the Level 1 core, adding methods and properties to nodes.
  • DOM Views — Defines different views for a document based on stylistic information.
  • DOM Events — Explains how to tie interactivity to DOM documents using events.
  • DOM Style — Defines how to programmatically access and change CSS styling information.
  • DOM Traversal and Range — Introduces new interfaces for traversing a DOM document and selecting specific parts of it.
  • DOM HTML — Builds on the Level 1 HTML, adding properties, methods, and new interfaces.

This chapter explores each of these modules except for DOM events, which are covered fully in Chapter 13.


DOM Level 3 also contains the XPath module and the Load and Save module. These are discussed in Chapter 18.


The purpose of the DOM Levels 2 and 3 Core is to expand the DOM API to encompass ...

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