BookMgnt.Controllers.BookController.Category C# (CSharp) Method

        public ActionResult Category(int? id, int? page)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }
            var book = db.Books.Where(a => a.CategoriesID == id);
            if (book == null)
            {
                return HttpNotFound();
            }
            int pageNum = (page ?? 1);
            var cate = db.Categories.Find(id);
            ViewBag.TitleCategory = cate.Name;
            return View(book.ToList().ToPagedList(pageNum, pageSize));
        }