public IHttpActionResult Put(string id, [FromBody] DuongDung p)
        {
            var recId     = new ObjectId(id);
            var DuongDung = duongDungs.Get(recId);

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

            duongDungs.Update(recId, p);
            return(Ok());
        }
 public IHttpActionResult Post([FromBody] DuongDung p)
 {
     duongDungs.Create(p);
     return(Ok(p));
 }