正常事件绑定与事件委托绑定

看下面的 案例，非原创，

<!doctype html>
<html>
<head>
  <meta http-equiv="Content-type" content="text/html; charset=utf-8"/>
  <script src="http://lib.sinaapp.com/js/jquery/1.9.1/jquery-1.9.1.min.js" type="text/javascript"></script>
  <style>
    div { width:60px; height:60px; margin:5px; float:left; }
    </style>

  <title>事件委托</title>
</head>
<body>

<h2>事件绑定的2种方式</h2>

<ul id="resources">
  <li><a href="http://opera.com/wsc">Opera Web Standards Curriculum</a></li>
  <li><a href="http://sitepoint.com">Sitepoint</a></li>
  <li><a href="http://alistapart.com">A List Apart</a></li>
  <li><a href="http://yuiblog.com">YUI Blog</a></li>
  <li><a href="http://blameitonthevoices.com">Blame it on the voices</a></li>
  <li><a href="http://oddlyspecific.com">Oddly specific</a></li>
</ul>
<script type="text/javascript">

//常规写法
(function() {
  var resources = document.getElementById('resources');
  var links = resources.getElementsByTagName('a');
  var all = links.length;
  for (var i = 0; i < all; i++) {
    //循环绑定
    links[i].addEventListener('click', handler, false);

  };
  function handler(e) {
    var x = e.target; 
    alert('addEventListener绑定: '+ x);
    e.preventDefault();
  };
})();

//事件委托
(function() {
  var resources = document.getElementById('resources');
  //绑定父元素
  resources.addEventListener('click', handler, false);
  function handler(e) {
    var x = e.target;
    if (x.nodeName.toLowerCase() === 'a') {
      alert('事件委托: ' + x);
      e.preventDefault();
    }
  };
})();




</script>

</body>
</html>

 

posted @ 2015-08-25 17:42  328201736  阅读(137)  评论(0)  编辑  收藏  举报