// GET: Clients/Edit/5
        public ActionResult Edit(int?id)  //éste método carga la vista de edición de un cliente existente
        {
            if (id == null)
            {
                return(new HttpStatusCodeResult(HttpStatusCode.BadRequest));
            }
            Client client = db.Clients.Find(id);

            if (client == null)
            {
                return(HttpNotFound());
            }

            var mapper = new ClientMapper();

            var vm = mapper.ClientToClientViewModel(client);

            vm.CityList = GetCitySelectList(client.CityId);

            return(View(vm));
        }