阻止事件冒泡和默认行为

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 window.onload=function(){
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 var b=document.getElementById("b");
 var c=document.getElementById("c");
 var c=document.getElementById("d");

     a.onclick=function(e){
         this.style.background="#000";    
         };

     b.onclick=function(e){
             this.style.background="#ccc";
             //阻止事件冒泡
             window.event.cancelBubble = true;//IE8以下
             e.stopPropagation();
         };

     d.onmousedown=function(e){
         //阻止默认事件，比如在chrome下图片有拖拽默认行为
         window.event.returnValue = false;
         e.preventDefault();
     }
 }

 

 </script>

参考于： http://www.jb51.net/article/36818.htm

 

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         <div id="c" style="width:100px;height:100px;background:yellow;margin:50px 0 0 50px;overflow:hidden;">
             <img src="240x240.jpg" width="50" height="50" id="d" />
         </div>
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