javascript添加删除事件封装

<script type="text/javascript">

var EventUtil = {

        addHandler: function (oElement, sEvent, fnHandler) {

              oElement.addEventListener ? oElement.addEventListener(sEvent, fnHandler, false) : oElement.attachEvent("on" + sEvent, fnHandler)      

        },

        removeHandler: function (oElement, sEvent, fnHandler) {

               oElement.removeEventListener ? oElement.removeEventListener(sEvent, fnHandler, false) : oElement.detachEvent("on" + sEvent, fnHandler)

        },

        addLoadHandler: function (fnHandler) {

               this.addHandler(window, "load", fnHandler)

        }

};

EventUtil.addLoadHandler(function () {

        var aBtn = document.getElementsByTagName("input");

       

        //为第一个按钮添加绑定事件

        EventUtil.addHandler(aBtn[1], "click", function () {

               EventUtil.addHandler(aBtn[0], "click", fnHandler);   

               aBtn[0].value = "我可以点击了"

        });

       

        //解除第一个按钮的绑定事件

        EventUtil.addHandler(aBtn[2], "click", function () {

               EventUtil.removeHandler(aBtn[0], "click", fnHandler);

               aBtn[0].value = "毫无用处的按钮"     

        });

       

        //事件处理函数

        function fnHandler ()

        {

               alert("事件绑定成功！")       

        }      

})

</script>