<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<script>
window.onload = function(){
var oDiv = document.getElementById(‘div1‘);
var oSpan = document.getElementById(‘span1‘);
bindEvent(oDiv , ‘click‘,function(){
alert(1);
});
bindEvent(oDiv , ‘click‘,function(){
alert(2);
});
bindEvent(oSpan , ‘show‘,function(){
alert(3);
});
bindEvent(oSpan , ‘show‘,function(){
alert(4);
});
bindEvent(oSpan , ‘hide‘,function(){
alert(5);
});
fireEvent(oSpan , ‘show‘); //3 , 4
};
function bindEvent(obj,events,fn){
//obj : 楼层
//events : 书架
//fn : 一本书
obj.listeners = obj.listeners || {};
obj.listeners[events] = obj.listeners[events] || [];
obj.listeners[events].push( fn );
if(obj.addEventListener){
obj.addEventListener(events,fn,false);
}
else{
obj.attachEvent(‘on‘+events,fn);
}
}
function fireEvent(obj,events){ //主动触发自定义事件
for(var i=0;i<obj.listeners[events].length;i++){
obj.listeners[events][i]();
}
}
</script>
</head>
<body>
<div id="div1">div</div>
<span id="span1">span</span>
</body>
</html>
原文：http://www.cnblogs.com/yanwen2015/p/4705412.html