js url参数截取及关闭浏览器tab方法

 function GetQueryString(username)
    {
         var reg = new RegExp("(^|&)"+ username +"=([^&]*)(&|$)");
         var r = window.location.search.substr(1).match(reg);
         if(r!=null)return  unescape(r[2]); return null;
    }


function CloseWin(){
		window.opener=null;
		window.open('about:blank','_self');
		window.close();
	}