public async Task <IHttpActionResult> CreateUser(User user) { if (!ModelState.IsValid) { return(BadRequest(ModelState)); } if (string.IsNullOrWhiteSpace(user.NickName) || string.IsNullOrWhiteSpace(user.Email) || string.IsNullOrWhiteSpace(user.Password)) { return(BadRequest()); } try { await db.CreateAUser(user); } catch { return(BadRequest()); } int?id = await db.Users .Where((u) => u.NickName == user.NickName) .Select((u) => u.UserID) .SingleOrDefaultAsync(); return(Json <int?>(id)); }