public ActionResult Details(int?id)
        {
            var Ebook = db.Ebooks_db.Find(id);

            ViewBag.Ebook = Ebook;
            var review = new EBook_Review_db()
            {
                EBookId = Ebook.Ebook_id
            };

            return(View("Details", review));
        }
        public ActionResult SendReview(EBook_Review_db review, double rating)
        {
            string mem_email = Session["mem_email"].ToString();

            review.DatePost = DateTime.Now;
            review.memberId = db.tbl_member.Single(a => a.mem_email.Equals(mem_email)).mem_id;
            review.ERating  = rating;
            db.EBook_Review_db.Add(review);
            db.SaveChanges();


            return(RedirectToAction("Details", "EBooks", new { id = review.EBookId }));
        }