public void CategoryUpdate()
        {
            var categories = _category.CollectCategoryList();
            var vehicle    = _vehicle.CollectRegisteredVehicleList().ToList();

            for (var i = 0; i < vehicle.Count; i++)
            {
                vehicle[i] = DefineCategory(categories, vehicle[i]);
                _vehicle.Update(vehicle[i]);
            }
        }
        public IActionResult Index(string sortOrder)
        {
            ViewBag.OwnerSortParam        = String.IsNullOrEmpty(sortOrder) ? "OwnerName_desc" : "";
            ViewBag.ManufacturerSortParam = sortOrder == "Manufacturer" ? "ManufacturerName_desc" : "Manufacturer";
            ViewBag.YearSortParam         = sortOrder == "Year" ? "Year_desc" : "Year";
            ViewBag.WeightSortParam       = sortOrder == "Weight" ? "Weight_desc" : "Weight";
            List <RegisteredVehicleListView> registeredVehiclesView = new List <RegisteredVehicleListView>();
            var registeredVehicles = _vehicle.CollectRegisteredVehicleList().AsQueryable <RegisteredVehicle>();

            switch (sortOrder)
            {
            case "OwnerName_desc":
                registeredVehicles = registeredVehicles.OrderByDescending(m => m.OwnerName);
                break;

            default:
                registeredVehicles = registeredVehicles.OrderBy(m => m.OwnerName);
                break;

            case "ManufacturerName_desc":
                registeredVehicles = registeredVehicles.OrderByDescending(m => m.Manufacturer);
                break;

            case "Manufacturer":
                registeredVehicles = registeredVehicles.OrderBy(m => m.Manufacturer);
                break;

            case "Year_desc":
                registeredVehicles = registeredVehicles.OrderByDescending(m => m.Year);
                break;

            case "Year":
                registeredVehicles = registeredVehicles.OrderBy(m => m.Year);
                break;

            case "Weight_desc":
                registeredVehicles = registeredVehicles.OrderByDescending(m => m.Weight);
                break;

            case "Weight":
                registeredVehicles = registeredVehicles.OrderBy(m => m.Weight);
                break;
            }

            registeredVehiclesView = _service.ConvertDataToListView(registeredVehicles.ToList());

            return(View(registeredVehiclesView));
        }