public ActionResult Display(int id)
        {
            Photo photo = context.FindPhotoById(id);

            if (photo == null)
            {
                return(HttpNotFound());
            }

            return(View("Display", photo));
        }
        public ActionResult Display(int id)
        {
            Photo p = context.FindPhotoById(id);

            if (p != null)
            {
                return(View("Display", p));
            }
            else
            {
                return(HttpNotFound());
            }
        }
        public ActionResult Detail(int id)
        {
            Photo photo = context.FindPhotoById(id);

            if (photo == null)
            {
                return(HttpNotFound());
            }
            else
            {
                return(View("Detail", photo));
            }
        }
        public Photo GetPhotoById(int id)
        {
            Photo photo = context.FindPhotoById(id);

            if (photo == null)
            {
                throw new HttpResponseException(HttpStatusCode.NotFound);
            }
            return(photo);
        }