package com.abdulqabiz.utils
{
       import flash.external.*;
       import flash.utils.*;

       public class QueryString
       {

               private var _queryString:String;
               private var _all:String;
               private var _params:Object;
               
               public function get queryString():String
               {
                       return _queryString;
               }
               public function get url():String
               {
                       return _all;
               }
               public function get parameters():Object
               {
                       return _params;
               }               

               
               public function QueryString()
               {
               
                       readQueryString();
               }

               private function readQueryString():void
               {
                       _params = {};
                       try
                       {
                               _all =  ExternalInterface.call("window.location.href.toString");
                               _queryString = ExternalInterface.call("window.location.search.substring", 1);
                               if(_queryString)
                               {
                               
                                       var params:Array = _queryString.split('&');
                                       var length:uint = params.length;
                                       
                                       for (var i:uint=0,index:int=-1; i<length; i++)
                                       {
                                               var kvPair:String = params[i];
                                               if((index = kvPair.indexOf("=")) > 0)
                                               {
                                                       var key:String = kvPair.substring(0,index);
                                                       var value:String = kvPair.substring(index+1);
                                                       _params[key] = value;
                                               }
                                       }
                               }
                       }catch(e:Error) { trace("Some error occured. ExternalInterface doesn't work in Standalone player."); }
               }

       }
}

example: public var qs:QueryString

qs = new QueryString(); qs.parameters.XXXX

trace(qs.url)

qet query string

ActionScript 3