private void btnSave_Click(object sender, RoutedEventArgs e)
 {
     try
     {
         bl.AddStock(new BO.Item
         {
             ItemID      = item.ItemID,
             Brand       = item.Brand,
             ModelNumber = item.ModelNumber,
             Description = item.Description,
             Price       = item.Price,
             Quantity    = item.Quantity,
         },
                     item.CostPrice);
     }
     catch (Exception ex)
     {
         MessageBox.Show(ex.Message);
     }
     Close();
 }