public IHttpActionResult PutBaiVietHD(int id, BaiVietHD baiVietHD)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            if (id != baiVietHD.MaBVHD)
            {
                return(BadRequest());
            }

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

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

            return(StatusCode(HttpStatusCode.NoContent));
        }
        public IHttpActionResult GetBaiVietHD(int id)
        {
            BaiVietHD baiVietHD = db.BaiVietHDs.Find(id);

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

            return(Ok(baiVietHD));
        }
        public IHttpActionResult PostBaiVietHD(BaiVietHD baiVietHD)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            db.BaiVietHDs.Add(baiVietHD);
            db.SaveChanges();

            return(CreatedAtRoute("DefaultApi", new { id = baiVietHD.MaBVHD }, baiVietHD));
        }
        public IHttpActionResult DeleteBaiVietHD(int id)
        {
            BaiVietHD baiVietHD = db.BaiVietHDs.Find(id);

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

            db.BaiVietHDs.Remove(baiVietHD);
            db.SaveChanges();

            return(Ok(baiVietHD));
        }