private void btnCancel_Click(object sender, EventArgs e)
{
CashierMenuForm menuPage = new CashierMenuForm(user, cartItems);
this.Hide();
menuPage.ShowDialog();
this.Close(); //close previous form
}
private void btnNextOrder_Click(object sender, EventArgs e)
{
CashierMenuForm cashierPage = new CashierMenuForm(user);
this.Hide();
cashierPage.ShowDialog();
this.Close();
}