Javascrpt冒泡事件

window.onload = function() {
    //冒泡事件就是有内到外，由下至上如冒泡般触发的顺序
    document.onclick = function(){
        alert(‘document‘);
    };
    document.documentElement.onclick = function(){
        alert(‘HTML‘);
    };
    document.body.onclick = function(){
        alert(‘body‘);
    };
    document.getElementById(‘box‘).onclick = function(){
        alert(‘div‘);
    };
    document.getElementById(‘input‘).onclick = function(evt){
        //阻止冒泡需要stopPropagation()方法
        var e = evt || window.event;
        alert(‘input‘);
        if(e.stopPropagation){
            e.stopPropagation();
        }else {
            e.cancelBubble = true;    //IE兼容
        }
        
    };
}