public ActionResult Add(SalesmanViewModel model)
        {
            AlertMessage alert = new AlertMessage();

            SalesmanBusiness business = new SalesmanBusiness();

            if (!ModelState.IsValid)
            {
                alert.Text = string.Join(System.Environment.NewLine, ModelState.Values
                                         .SelectMany(v => v.Errors)
                                         .Select(e => e.ErrorMessage));
            }
            else
            {
                business.SetUserAuth(ViewBag.UserAuth);

                alert = business.Add(model);
            }

            TempData["AlertMessage"] = alert;

            if (alert.Status == 1)
            {
                return(RedirectToAction("Index"));
            }

            return(View("Edit", model));
        }