js實現跨瀏覽器添加事件與移除事件怎樣做才最優？

一般的相容做法，如下：

跨瀏覽器添加事件

//跨瀏覽器添加事件
    function addEvent(obj,type,fn){
        if(obj.addEventListener){
            obj.addEventListener(type,fn,false);
        }else if(obj.attachEvent){//IE
            obj.attchEvent('on'+type,fn);
        }
    }

跨瀏覽器移除事件

//跨瀏覽器移除事件
function removeEvent(obj,type,fn){
    if(obj.removeEventListener){
        obj.removeEventListener(type,fn,false);
    }else if(obj.detachEvent){//相容IE
        obj.detachEvent('on'+type,fn);
    }
}

推薦寫法

    function addEvent( obj, type, fn ) {
      if ( obj.attachEvent ) {
        obj['e'+type+fn] = fn;
        obj[type+fn] = function(){obj['e'+type+fn]( window.event );}
        obj.attachEvent( 'on'+type, obj[type+fn] );
      } else
        obj.addEventListener( type, fn, false );
    }
    function removeEvent( obj, type, fn ) {
      if ( obj.detachEvent ) {
        obj.detachEvent( 'on'+type, obj[type+fn] );
        obj[type+fn] = null;
      } else
        obj.removeEventListener( type, fn, false );
    }

參考地址：

addEvent() recoding contest entry

addEvent() – Follow Up