/// <summary> /// calculates the customer's change (total amount - customer payment), /// this will determine whether or not the cashier can proceed to the next form /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void CalculateButton_Click(object sender, EventArgs e) { GlobalUtilities.setCashPayment(cashTextBox.Text); GlobalUtilities.setCreditPayment(creditTextBox.Text); GlobalUtilities.setDebitPayment(debitTextBox.Text); GlobalUtilities.setCheckPayment(checkTextBox.Text); GlobalUtilities.setSalaryDeductionPayment(salaryDeductionTextBox.Text); GlobalUtilities.setTotalCustomerPayment(); GlobalUtilities.setTotalChange(); changeTextBox.Text = String.Format("{0:n}", GlobalUtilities.getTotalChange()); totalCustomerPaymentTextBox.Text = String.Format("{0:n}", (Double.Parse(GlobalUtilities.getCashPayment()) + Double.Parse(GlobalUtilities.getCreditPayment()) + Double.Parse(GlobalUtilities.getDebitPayment()) + Double.Parse(GlobalUtilities.getCheckPayment()) + Double.Parse(GlobalUtilities.getSalaryDeductionPayment())).ToString()); if (Double.Parse(GlobalUtilities.getTotalChange()) >= 0) { proceedButton.Enabled = true; } else { proceedButton.Enabled = false; } }