JS获取URL参数

 function GetRequest()
         {
            var url = location.search; //获取url中"?"符后的字串
            var theRequest = new Object();
            if (url.indexOf("?") != -1) {
            var str = url.substr(1);
            strs = str.split("&");
            for(var i = 0; i < strs.length; i ++)
            {
              theRequest[strs[i].split("=")[0]]=unescape(strs[i].split("=")[1]);
            }
           }
          return theRequest;
       }

var Request = new Object();
Request = GetRequest();
if (typeof(Request['__Topic']) != "undefined")
{
   document.getElementById('__Topic').value = Request['__Topic'];
   if( Request['__first'] == 1)
   {
        document.getElementById('SearchForm').submit();
    }
 

}