阻止事件冒泡（stopPropagation和cancelBubble）

<div id="divId1" style="width:500px;height:500px;background-color:#3ac;text-align:center;" align="center">
            <div id="divId2"  style="width:400px;height:400px;background-color:#f1f; margin:0 auto;">开始啦</div>
        </div>

        document.getElementById(‘divId1‘).onclick = function(){
            alert(‘divId1‘);
        }
var eleDiv2 = document.getElementById(‘divId2‘);
        if(eleDiv2.addEventListener){
            eleDiv2.addEventListener(‘click‘,function(evt){
                alert(‘divId2‘);
                evt.stopPropagation();
            },false);
        }else{
            eleDiv2.attachEvent(‘onclick‘,function(evt){
                alert(‘divId2‘);
                evt.cancelBubble = true;
            });
        }