private void _add_Click(object sender, RoutedEventArgs e)
 {
     AddShipper ship = new AddShipper(dbOperation, shipperflag);
     ship.ShowDialog();
 }  
        private void _add_Click(object sender, RoutedEventArgs e)
        {
            AddShipper ship = new AddShipper(dbOperation, shipperflag);

            ship.ShowDialog();
        }