public void addComment(Comment comment)
 {
     if (IDC == 0)
     {
         Comments = new List<Comment>();
     }
     Comments.Add(comment);
     IDC++;
 }
        // POST api/comment
        public HttpResponseMessage Post(Comment comment)
        {
            //User u = db.Users.Where(
                    //(p) => p.UserName.ToLower() == comment.UserName.ToLower()).First<User>();
            //db.Users.Remove(u);

            //u.addComment(comment);
            //db.Entry(u).State = EntityState.Modified;
            //db.Users.Add(u);
            db.Comments.Add(comment);
            try
            {
                db.SaveChanges();
            }
            catch (DbUpdateConcurrencyException)
            {
                return Request.CreateResponse(HttpStatusCode.NotFound);
            }
            return Request.CreateResponse(HttpStatusCode.OK);
        }