static BookProviders()
 {
     Instance = new BookProviders();
     Instance.AllBooks = new List<Books>();
     for (int i = 1; i <= 50; i++)
     {
         Books book = new Books() { Id = i, Name = String.Format("Book #{0}", i), Price = i };
         Instance.AllBooks.Add(book);
     }
     Counter = 0;
 }
 public ActionResult Create(Books book)
 {
     if (book.Name == null || book.Price == null)
     {
         return View("CreateError");
     }
     else if (book != null && this.ModelState.IsValid)
     {
         book.Id = ++BookProviders.Counter + 50;
         BookProviders.Instance.AllBooks.Add(book);
         return RedirectToAction("Show", new { pageNumber = 1 });
     }
     else
     {
         return RedirectToAction("Show", new { pageNumber = 1 });
     }
 }
        public ActionResult Edit(Books book)
        {
            if (book.Name != null && book.Price != null && this.ModelState.IsValid)
            {
                Books updatedBook = BookProviders.Instance.AllBooks.SingleOrDefault(b => b.Id == book.Id);
                if (updatedBook != null)
                {
                    updatedBook.Name = book.Name;
                    updatedBook.Price = book.Price;
                }
            }
            else
            {
                return View("EditError");
            }

            return RedirectToAction("Show", new { pageNumber = 1 });
        }