Dynamic HTML: The Definitive Reference, 3rd Edition

Chapter 8. DOM Method Index

Entries in the following index are arranged alphabetically by scriptable object methods. Look up a method to find out which document objects support it. You need to be aware, however, of what support means within the context of the way that browser makers and the W3C DOM specify the inner workings of their models using object-oriented approaches. For example, the list of objects that “support” the user-interface-oriented focus( ) method includes several nonrendered HTML element objects, such as head and meta. Inside the browsers, many methods are defined for a generic HTML element, and all elements, regardless of their purpose, inherit those methods. Clearly, attempting to set focus to nonrendered elements is a waste of time in actual development; but because these element objects expose the focus( ) method, they appear in that method’s list.

Omitting this information here could cause equally serious problems for scripters who write object- and method-detection scripts. It’s better to know that a method is defined (that is, its value type is not undefined) for a particular object than to be misled into thinking that its omission means that the method is undefined for the object.

This listing is a union of methods defined for objects in Internet Explorer, pre-Mozilla Netscape Navigator, Mozilla, Safari, Opera, and implemented objects from Web Forms 2.0 and the W3C DOM Levels 2 and 3. The same method name may mean different things for different objects. ...