public ActionResult DiscountFees(StudentSearchViewModel userInput)
        {
            TransactionHelper helper = new TransactionHelper();
            string            error  = "";

            HostelTransactionViewModel viewModel = helper.ConstructViewModelForHostelFeeDiscount(userInput.bid, out error);

            if (viewModel != null)
            {
                // generate the list of account heads to be displayed and add it to the view bag
                ViewBag.acHeadList = new SelectList(helper.GetAccountHeads(), "id", "val");

                // generate the list of payment types to be displayed and add it to the view bag
                ViewBag.paymentTypeList = new SelectList(helper.GetPaymentTypes(true), "id", "val", "4");

                //generate the list of academic years to be displayed and add it to the view bag
                ViewBag.academicYearList = new SelectList(helper.GetValidAcademicYears(viewModel.year), DateTime.Now.Year + "");

                // display the view
                return(PartialView("_AddDiscount", viewModel));
            }

            return(Content(error));
        }