private void bnAddCustomer_Click(object sender, EventArgs e) { try { customerDialog.ClearDisplayItems(); //BookShopControl.findDuplicateCustomers(customerDialog.UserName); switch (customerDialog.Display()) { case DialogReturn.Cancel: return; case DialogReturn.Done: BookShopControl.addNewCustomer(customerDialog.FirstName, customerDialog.LastName, customerDialog.UserName, customerDialog.Password, customerDialog.EMailAddress, customerDialog.Address, customerDialog.TelephoneNumber); break; default: return; } } catch (BookShopException bsex) { MessageBox.Show(this, bsex.ErrorMessage); } }