public IActionResult Index(SortState sortState = SortState.CarMarkNameAsc, int page = 1)
        {
            CarMarksFilterViewModel filter = HttpContext.Session.Get <CarMarksFilterViewModel>(filterKey);

            if (filter == null)
            {
                filter = new CarMarksFilterViewModel {
                    CarMarkName = string.Empty
                };
                HttpContext.Session.Set(filterKey, filter);
            }

            string modelKey = $"{typeof(CarMark).Name}-{page}-{sortState}-{filter.CarMarkName}";

            if (!cache.TryGetValue(modelKey, out CarMarkViewModel model))
            {
                model = new CarMarkViewModel();

                IQueryable <CarMark> carMarks = GetSortedEntities(sortState, filter.CarMarkName);

                int count    = carMarks.Count();
                int pageSize = 10;
                model.PageViewModel = new PageViewModel(page, count, pageSize);

                model.Entities                = count == 0 ? new List <CarMark>() : carMarks.Skip((model.PageViewModel.CurrentPage - 1) * pageSize).Take(pageSize).ToList();
                model.SortViewModel           = new SortViewModel(sortState);
                model.CarMarksFilterViewModel = filter;

                cache.Set(modelKey, model);
            }

            return(View(model));
        }
        public IActionResult Index(CarMarksFilterViewModel filterModel, int page)
        {
            CarMarksFilterViewModel filter = HttpContext.Session.Get <CarMarksFilterViewModel>(filterKey);

            if (filter != null)
            {
                filter.CarMarkName = filterModel.CarMarkName;

                HttpContext.Session.Remove(filterKey);
                HttpContext.Session.Set(filterKey, filter);
            }

            return(RedirectToAction("Index", new { page }));
        }