function ajax()
{
   //---------------------
   // Private Declarations
   //---------------------
   var _request = null;
   var _this = null;
       
   //--------------------
   // Public Declarations
   //--------------------
   this.GetResponseXML = function()
   {
      return (_request) ? _request.responseXML : null;
   }
       
   this.GetResponseText = function()
   {
      return (_request) ? _request.responseText : null;
   }
       
   this.GetRequestObject = function()
   {
      return _request;
   }
       
   this.InitializeRequest = function(Method, Uri)
   {
      _InitializeRequest();
      _this = this;
               
      switch (arguments.length)
      {
         case 2:
            _request.open(Method, Uri);
            break;
                               
         case 3:
            _request.open(Method, Uri, arguments[2]);
            break;
      }
               
      if (arguments.length >= 4) _request.open(Method, Uri, arguments[2], arguments[3]);
      this.SetRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
   }
       
   this.SetRequestHeader = function(Field, Value)
   {
      if (_request) _request.setRequestHeader(Field, Value);
   }
       
   this.Commit = function(Data)
   {
      if (_request) _request.send(Data);
   }
       
   this.Close = function()
   {
      if (_request) _request.abort();
   }
       
   //---------------------------
   // Public Event Declarations.
   //---------------------------
   this.OnUninitialize = function() { };
   this.OnLoading = function() { };
   this.OnLoaded = function() { };
   this.OnInteractive = function() { };
   this.OnSuccess = function() { };
   this.OnFailure = function() { };
       
   //---------------------------
   // Private Event Declarations
   //---------------------------
   function _OnUninitialize() { _this.OnUninitialize(); };
   function _OnLoading() { _this.OnLoading(); };
   function _OnLoaded() { _this.OnLoaded(); };
   function _OnInteractive() { _this.OnInteractive(); };
   function _OnSuccess() { _this.OnSuccess(); };
   function _OnFailure() { _this.OnFailure(); };

   //------------------
   // Private Functions
   //------------------
   function _InitializeRequest()
   {
      _request = _GetRequest();
      _request.onreadystatechange = _StateHandler;
   }
       
   function _StateHandler()
   {
      switch (_request.readyState)
      {
         case 0:
            window.setTimeout("void(0)", 100);
            _OnUninitialize();
            break;
                               
         case 1:
            window.setTimeout("void(0)", 100);
            _OnLoading();
            break;
                               
         case 2:
            window.setTimeout("void(0)", 100);
            _OnLoaded();
            break;
                       
         case 3:
            window.setTimeout("void(0)", 100);
            _OnInteractive();
            break;
                               
         case 4:
            if (_request.status == 200)
               _OnSuccess();
            else
               _OnFailure();
                                       
            return;
            break;
      }
   }
       
   function _GetRequest()
   {
      var obj;
               
      try
      {
        // Firefox, Opera 8.0+, Safari
        obj=new XMLHttpRequest();
      }
      catch (e)
      {
        // Internet Explorer
        try
        {
          obj=new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch (e)
        {
          try
          {
            obj=new ActiveXObject("Microsoft.XMLHTTP");
          }
          catch (e)
          {
            alert("Your browser does not support AJAX!");
            return null;
          }
        }
      }
      /*
      try
      {
         obj = new XMLHttpRequest();
      }
      catch (error)
      {
         try
         {
            obj = new ActiveXObject("Microsoft.XMLHTTP");
         }
         catch (error)
         {
            return null;
         }
      }
      */       
      return obj;
   }
}