Event Handler Properties (Dynamic HTML: The Definitive Reference, 2nd Edition)

Dynamic HTML: The Definitive Reference, 2rd Ed.

9.4. Event Handler Properties

Objects that can receive events have event handlers listed in their main entries. Because this chapter focuses on the scriptable aspects of HTML elements, the event handlers are listed in their lowercase property form—the form used to assign function references to event handlers in script statements. See Section 6.3 in Chapter 6,for details on this event handler format.

The selection of event handler properties listed for each object is based on a couple of factors. First, just as most HTML 4.0 elements have intrinsic events associated with them, those same events are listed in this chapter with the objects that reflect the html element. As such, it may seem odd that an element that has almost no visual presence on a page has keyboard and mouse events. Those events are listed just the same, even though the likelihood of your scripting them is next to nil.

Second, the Internet Explorer and W3C DOM event bubbling models (see Chapter 6) dictate that it is possible for an event from one element to bubble up through the element containment hierarchy all the way to a root node or element. This means that essentially every event that can appear in the most nested element (such as the events related to Microsoft's data binding facilities in Win32) is also available in all elements higher up the containment chain. In other words, virtually every element that acts as a container can have virtually every bubbling event type associated with it. You can read more about the characteristics of each event type in Chapter 10.