private void Button_Add_Click(object sender, RoutedEventArgs e)
 {
     try
     {
         PrepareObject();
         using (var data = new DataServiceClient())
         {
             data.AddDeal(viewDeal);
         }
         MessageBox.Show("Transaction successful !");
     }
     catch (Exception ex)
     {
         MessageBox.Show("Error !");
     }
     this.Close();
 }