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Event capturing

Mozilla 1.0 and higher also supports event bubbling, but to another level. Just like IE 6.0, it supports

events on the

<html/>

element. However, events bubble all the way up to the window object (which is

not a part of the DOM). Using the previous example in Mozilla, clicking the

<div/>

element causes the

event bubbling displayed in Figure 9-3.

Figure 9-3

Event capturing

While Internet Explorer 4.0 used event bubbling, Netscape Navigator 4.0 used an alternate solution

called

event capturing

. Event capturing is just the opposite of bubbling; events fire from the least-specific

object (the

document

object) to the most specific (it was also possible to capture events at the window

level, but that has to be specified explicitly by the developer). Netscape Navigator also doesn’t expose

many elements on the page to events.

Referring again to the previous example, if a user clicks the

<div/>

element using Netscape 4.x, the

event takes the following path:

document

<div/>

body

html

div

div 1

document 4

window

window 5

If you are unsure whether your users will be using IE 5.5 or IE 6.0, it is best to avoid

handling events at the

<html/>

element level.

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