public ActionResult Edit(int id, EditEventModel model)
 {
     if (ModelState.IsValid){
         service.UpdateEvent(id, model);
         return RedirectToAction("Index");
     }
     return View(service.GetEditEventModel(id));
 }
 public void UpdateEvent(int eventId, EditEventModel model)
 {
     var evt = GetEvent(eventId);
     model.MapTo(evt);
     repository.SaveChanges();
 }