public ActionResult Edit(EditViewModel editViewModel)
        {
            if (editViewModel == null)
            {
                throw new HttpException(400, "Bad Request");
            }

            var documentCategory = DocumentCategoryService.FindById(editViewModel.DocumentCategoryId);
            if (documentCategory == null)
            {
                throw new HttpException(404, "Not Found");
            }

            documentCategory.Name = editViewModel.Name;
            documentCategory.Description = editViewModel.Description;
            DocumentCategoryService.UpdateDocumentCategory(documentCategory);

            TempData["DocumentCategoryId"] = documentCategory.DocumentCategoryId;
            TempData["DocumentCategoryName"] = documentCategory.Name;
            TempData["Message"] = RolesMessage.EditSuccess;
            return RedirectToAction("index", "documentcategories");
        }
        public ActionResult Edit(int? id)
        {
            if (id == null)
            {
                throw new HttpException(400, "Bad Request");
            }

            var documentCategory = DocumentCategoryService.FindById(id.Value);
            if (documentCategory == null)
            {
                throw new HttpException(404, "Not Found");
            }

            var editViewModel = new EditViewModel()
            {
                DocumentCategoryId = documentCategory.DocumentCategoryId,
                Name = documentCategory.Name,
                Description = documentCategory.Description
            };
            return View(editViewModel);
        }