详解javascript跨浏览器事件处理程序【javascript】

                function $(id){      return document.getElementById(id);    }     var EventUtil={      fnCount:0      ,fnData:{}      ,addHandler:function(element,type,handler){        this.fnCount++;        handler.fid = this.fnCount;        var _fn = handler;        handler = function(){          _fn.call(element);        };        this.fnData[this.fnCount] = handler;         if(element.addEventListener){          element.addEventListener(type,handler,false);        }  else if(element.attachEvent){          element.attachEvent("on"+type,handler);        }  else {          element["on"+type]=handler;        }      }      ,removeHandler:function(element,type,handler){        handler = this.fnData[handler.fid];        if(element.removeEventListener){            element.removeEventListener(type,handler,false);        }else if(element.detachEvent){            element.detachEvent("on"+type,handler);        }else{            element["on"+type]=null;        }      }    }     var btn=$("myBtn");    var unbtn = $('unlisten');    var bindFn1=function(){      alert(this.id);    };    var bindFn2=function(){      alert('2');    };     EventUtil.addHandler(btn,"click",bindFn1);    EventUtil.addHandler(btn,"click",bindFn2);    //EventUtil.removeHandler(btn,"click",bindFn1);    EventUtil.addHandler(unbtn,"click",function(){      EventUtil.removeHandler(btn,"click",bindFn1);    });