javascript-回归原生基础

 //添加事件监听兼容函数
 function addHandler(target, eventType, handler){
     if(target.addEventListener){//主流浏览器
         addHandler = function(target, eventType, handler){
             target.addEventListener(eventType, handler, false);
         };
     }else{//IE
         addHandler = function(target, eventType, handler){
             target.attachEvent("on"+eventType, handler);
         };
     }
     //执行新的函数
     addHandler(target, eventType, handler);
 }
 //删除事件监听兼容函数
 function removeHandler(target, eventType, handler){
     if(target.removeEventListener){//主流浏览器
         removeHandler = function(target, eventType, handler){
             target.removeEventListener(eventType, handler, false);
         }
     }else{//IE
         removeHandler = function(target, eventType, handler){
             target.detachEvent("on"+eventType, handler);
         }
     }
     //执行新的函数
     removeHandler(target, eventType, handler);
 }