Javascript Dom 事件冒泡

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<title>Bubble in JavaScript DOM</title>
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<h1>Bubble in JavaScript DOM</h1>
<p>DOM树的结构是:</p>
<pre><code>
UL
  - LI
     - A
   - SPAN
</code></pre>
<div>
 <ul>
  <li><a href="#"><span>Bubbllllllllllllllle</span></a></li>
  <li><a href="#"><span>Bubbllllllllllllllle</span></a></li>
 </ul>
</div>
<textarea></textarea>
<p>鼠标进入UL的任何一个子元素,如果不停止冒泡,我们从UL到SPAN都定义了鼠标悬停(<code>mouseover</code>)事件,这个事件会上升了UL,从而从鼠标所进入的元素到UL元素都会有红色的边。</p>
<div>
 <ul>
  <li><a href="#"><span>Bubbllllllllllllllle</span></a></li>
  <li><a href="#"><span>Bubbllllllllllllllle</span></a></li>
 </ul>
</div>
<p>如果停止冒泡,事件不会上升,我们就可以获取精确的鼠标进入元素。</p>
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posted @ 2010-10-13 16:01  gsbhz  阅读(186)  评论(0编辑  收藏  举报