private void retrieveBut_Click(object sender, RoutedEventArgs e)
        {
            string message = null;
            bool   success = false;

            if (Disable)
            {
                message = "If you want to retrieve the car, you should manually enable the slot.";
                System.Windows.MessageBox.Show(message, "Confirmaton", MessageBoxButton.OK, MessageBoxImage.Information);
            }
            else
            {
                message = "Do you want to retrieve the car?";
            }

            if (!Disable && System.Windows.MessageBox.Show(message, "Confirmaton", MessageBoxButton.YesNo, MessageBoxImage.Information) == MessageBoxResult.Yes)
            {
                if (objGeneralDba.InsertQueue(objCarData.CardId, 0))
                {
                    this.retrieveEventHandler(sender, new EventArgs());
                }
                else
                {
                    System.Windows.MessageBox.Show("Error when sending retrieval request");
                }
            }
        }
 private void retrive_but_Click(object sender, RoutedEventArgs e)
 {
     if (objGeneralDba == null)
         objGeneralDba = new GeneralDba();
     if (RequestType != 0)
     {
         MessageBoxResult messageBoxResult
                 = System.Windows.MessageBox.Show("Do you want to Retrieve?", "Retrieve Confirmation", System.Windows.MessageBoxButton.YesNo);
         if (messageBoxResult == MessageBoxResult.Yes)
         {
             //4: for transfer
             objGeneralDba.InsertQueue(this.CardId, 0);
             this.Close();
         }
     }
     
 }