private void BtnAddPaymentType_Click(object sender, RoutedEventArgs e)
        {
            var paymentTypeDescription     = txtPaymentTypeDescription.Text;
            var paymentTypeLongDescription = txtPaymentTypeLongDescription.Text;

            if (string.IsNullOrWhiteSpace(paymentTypeDescription))
            {
                MessageBox.Show("Code is blank");
            }
            if (string.IsNullOrWhiteSpace(paymentTypeLongDescription))
            {
                MessageBox.Show("Description is blank");
            }


            var result = paymentTypeCommand.Add(
                paymentTypeDescription, paymentTypeLongDescription);

            if (result.IsFailure)
            {
                MessageBox.Show(result.Error);
            }

            if (result.IsSuccess)
            {
                if (PropertyChanged != null)
                {
                    PropertyChanged(this, new PropertyChangedEventArgs("PaymentType"));
                    MessageBox.Show("Payment Type Added");
                }
            }
        }
        public IActionResult OnPost()
        {
            if (!ModelState.IsValid)
            {
                return(Page());
            }

            if (PaymentType.Id != Guid.Empty)
            {
                paymentTypeCommand.Update(PaymentType);
            }
            else
            {
                var result = paymentTypeCommand.Add(PaymentType.Description, PaymentType.LongDescription);

                if (result.IsFailure)
                {
                    TempData["Error"] = result.Error;
                    return(Page());
                }
            }

            return(RedirectToPage("./Detail", new { paymenttypeid = PaymentType.Id }));
        }