private void bunifuCheckbox_BorrowedBookCode_Click(object sender, EventArgs e) { if (manager.IsCorrectBookBorrowOrder(bunifuCustomTextbox_BorrowedBookCode.Text)) { Order borrowOrderInfo = manager.GetOrderFromID(bunifuCustomTextbox_BorrowedBookCode.Text); ReturnBookOrder returnBookOrder = new ReturnBookOrder(); int lateDays = DateTime.Now.CompareTo(borrowOrderInfo.DateCreated.Value.Date) - ParameterManager.GetMaxBookBorrowDays(); returnBookOrder.LateDays = (lateDays < 0) ? 0 : lateDays; returnBookOrder.BorrowOrderID = bunifuCustomTextbox_BorrowedBookCode.Text; DisplayReturnOrderInfo(returnBookOrder); bunifuMetroTextbox_GrandTotal.Text = "0"; double payment = double.Parse(borrowOrderInfo.TotalPayment.ToString()); UpdateTotalPayment(-payment); if (lateDays > 0) { if (payment < 300000) { UpdateTotalPayment(lateDays * ParameterManager.getLateFee(1)); } else if (payment < 700000) { UpdateTotalPayment(lateDays * ParameterManager.getLateFee(2)); } else { UpdateTotalPayment(lateDays * ParameterManager.getLateFee(3)); } } bunifuCustomTextbox_VIP.Text = manager.GetVipIDInOrder(borrowOrderInfo.OrderID); bunifuCheckbox_VIPChecker.Checked = true; bunifuCheckbox_VIPChecker.Enabled = false; bunifuCustomTextbox_VIP.Enabled = false; bunifuImageButton_ChooseBook.Enabled = false; bunifuImageButton_ChooseDish_Drink.Enabled = false; bunifuCheckbox_BorrowedBookCode.Enabled = false; } else { ErrorManager.MessageDisplay("Incorrect book borrow order ID", "", "Incorrect info. Plese recheck."); bunifuCheckbox_BorrowedBookCode.Checked = false; } }