js跨浏览器的事件处理函数

/*
  跨浏览器的事件处理函数
*/

var EventUtil = {

    addHandler : function(element,type,handler){
        if(element.addEventListener){
            element.addEventListener(type,handler,false);
        }else if(element.attachEvent){
            element.attachEvent('on'+type,handler);
        }else{
            element['on'+type] = handler;
        }

    },

    removeHandler : function(element,type,handler){
        if(element.removeEventListener){
            element.removeEventListener(type,handler,false);
        }else if(element.detachEvent){
            element.detachEvent('on'+type,handler);
        }else{
            element['on'+type] = null;
        }
    }
}

var btn = document.getElementById('button');
var handler = function(){
    alert('click');
};

EventUtil.addHandler(btn,'click',handler);