腾讯异步加载js代码 qq.com

<script type="text/javascript">   
var MiniSite=new Object();   
MiniSite.Browser={   
    ie:/msie/.test(window.navigator.userAgent.toLowerCase()),   
    moz:/gecko/.test(window.navigator.userAgent.toLowerCase()),   
    opera:/opera/.test(window.navigator.userAgent.toLowerCase()),   
    safari:/safari/.test(window.navigator.userAgent.toLowerCase())   
};   
MiniSite.JsLoader={   
    load:function(sUrl,fCallback){   
        var _script=document.createElement('script');   
        _script.setAttribute('charset','gb2312');   
        _script.setAttribute('type','text/javascript');   
        _script.setAttribute('src',sUrl);   
        document.getElementsByTagName('head')[0].appendChild(_script);   
        if(MiniSite.Browser.ie){   
            _script.onreadystatechange=function(){   
                if(this.readyState=='loaded'||this.readyStaate=='complete'){   
                    fCallback();   
                }   
            };   
        }else if(MiniSite.Browser.moz){   
            _script.onload=function(){   
                fCallback();   
            };   
        }else{   
            fCallback();   
        }   
    }   
};   
 
MiniSite.JsLoader.load("http://www.aaaa.com/templets/default/js/imgadplayer.js",function(){M();});   
</script>