public ActionResult Edit(CalendarModel model)
        {
            var calendar = _calendarRepository.GetById(model.Id);

            if (ModelState.IsValid)
            {
                calendar = model.ToEntity(calendar);

                //always set IsNew to false when saving
                calendar.IsNew = false;
                //update attributes
                _calendarRepository.Update(calendar);

                //commit all changes
                this._dbContext.SaveChanges();

                //notification
                SuccessNotification(_localizationService.GetResource("Record.Saved"));
                return(new NullJsonResult());
            }
            else
            {
                return(Json(new { Errors = ModelState.SerializeErrors() }));
            }
        }