/// <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;
}
}