function GetParam(name){
   var start=location.search.indexOf("?"+name+"=");
   if (start<0) start=location.search.indexOf("&"+name+"=");
   if (start<0) return '';
   start += name.length+2;
   var end=location.search.indexOf("&",start)-1;
   if (end<0) end=location.search.length;
   var result='';
   for(var i=start;i<=end;i++) {
    var c=location.search.charAt(i);
    result=result+(c=='+'?' ':c);
   }
   return unescape(result);
}