function GetQueryString(name) {

    var reg = new RegExp("(^|&)" + name + "=([^&]*)(&|$)","i");

    var r = window.location.search.substr(1).match(reg);

    if (r!=null) return (r[2]); return null;

 }

 alert(GetQueryString("参数名1"));

 alert(GetQueryString("参数名2"));

 alert(GetQueryString("参数名3"));