public async Task <IHttpActionResult> PutAuthor(int id, Author author)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            if (id != author.AuthorId)
            {
                return(BadRequest());
            }

            db.Entry(author).State = EntityState.Modified;

            try
            {
                await db.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!AuthorExists(id))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(StatusCode(HttpStatusCode.NoContent));
        }
        public void Put(int id, [FromBody] Author itemNew)
        {
            BookStoreDataContext db = new BookStoreDataContext();
            var item = db.Authors.SingleOrDefault(p => p.AuthorID.Equals(id));

            item.Name = itemNew.Name;

            db.Update(item);
            db.SaveChangesAsync();
        }
        public void Put(int id, [FromBody] Book itemNew)
        {
            BookStoreDataContext db = new BookStoreDataContext();
            var item = db.Books.SingleOrDefault(p => p.ISBN.Equals(id));

            item.CategoryID  = itemNew.CategoryID;
            item.Title       = itemNew.Title;
            item.Photo       = itemNew.Photo;
            item.PublishDate = itemNew.PublishDate;
            item.Price       = itemNew.Price;
            item.Quantity    = itemNew.Quantity;

            db.Update(item);
            db.SaveChangesAsync();
        }