public ActionResult SubscriptionUpdate(NewsLetterSubscriptionModel model, GridCommand command)
        {
            if (!_permissionService.Authorize(StandardPermissionProvider.ManageNewsletterSubscribers))
                return AccessDeniedView();

            if (!ModelState.IsValid)
            {
                //display the first model error
                var modelStateErrors = this.ModelState.Values.SelectMany(x => x.Errors).Select(x => x.ErrorMessage);
                return Content(modelStateErrors.FirstOrDefault());
            }

            var subscription = _newsLetterSubscriptionService.GetNewsLetterSubscriptionById(model.Id);
            subscription.Email = model.Email;
            subscription.Active = model.Active;
            _newsLetterSubscriptionService.UpdateNewsLetterSubscription(subscription);

            return SubscriptionList(command, new NewsLetterSubscriptionListModel());
        }
        public ActionResult SubscriptionUpdate(NewsLetterSubscriptionModel model, GridCommand command)
        {
            if (!_permissionService.Authorize(StandardPermissionProvider.ManageNewsletterSubscribers))
                return AccessDeniedView();

            var subscription = _newsLetterSubscriptionService.GetNewsLetterSubscriptionById(model.Id);
            subscription.Email = model.Email;
            subscription.Active = model.Active;
            _newsLetterSubscriptionService.UpdateNewsLetterSubscription(subscription);

            return SubscriptionList(command, new NewsLetterSubscriptionListModel());
        }