public ActionResult ChangeDiscount(int id, int?maxDiscount, int?stepDiscount) { var customer = _managerService.GetCustomerById(id); var customerViewModel = MappingViewModel.MapCustomerViewModel(customer); if (Request.HttpMethod == "POST") { if (maxDiscount == null) { ModelState.AddModelError("maxDiscount", "Please enter max discount"); } if (stepDiscount == null) { ModelState.AddModelError("stepDiscount", "Please enter step discount"); } if (ModelState.IsValid) { customer.StepDiscount = stepDiscount.Value; customer.MaxDiscount = maxDiscount.Value; _managerService.ChangeDiscountCustomer(customer); SLogger.InfoToFile($"Manager change discount customer id: {customer.Id}"); var messageInfo = new MessageViewModel() { Status = "success", Info = $"Changed discount for {customer.Name}" }; return(RedirectToAction("Index", messageInfo)); } else { return(View(customerViewModel)); } } else { return(View(customerViewModel)); } }