public IHttpActionResult PutCommentBook(int id, CommentBook commentBook)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            if (id != commentBook.CommentID)
            {
                return(BadRequest());
            }

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

            try
            {
                db.SaveChanges();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!CommentBookExists(id))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(StatusCode(HttpStatusCode.NoContent));
        }
        public IHttpActionResult PostCommentBook(CommentBook commentBook)
        {
            db.CommentBooks.Add(commentBook);
            db.SaveChanges();

            return(CreatedAtRoute("DefaultApi", new { id = commentBook.CommentID }, commentBook));
        }
        public IHttpActionResult DeleteCommentBook(int id)
        {
            CommentBook commentBook = db.CommentBooks.Find(id);

            if (commentBook == null)
            {
                return(NotFound());
            }

            db.CommentBooks.Remove(commentBook);
            db.SaveChanges();

            return(Ok(commentBook));
        }