public async Task <IActionResult> Create(SlideShowViewModel viewModel) { if (ModelState.IsValid) { if (await _slideShowService.CheckExistTitleAsync(viewModel.Id, viewModel.Title)) { ModelState.AddModelError(nameof(viewModel.Title), "عنوان وارد شده تکراری است"); return(View(viewModel)); } var result = await _slideShowService.InsertAsync(viewModel); if (result) { return(RedirectToAction("Index", "SlideShow")); } return(View(viewModel)); } return(View(viewModel)); }