public ActionResult Index(string option)
        {
            if (option != null)
            {
                switch (option.ToLower())
                {
                case "wordform":
                {
                    _viewModel = new WordFormViewModel();
                    CreateLayoutView("Từ vựng");
                    break;
                }

                case "listening":
                {
                    _viewModel = new ListeningViewModel();
                    CreateLayoutView("Tập nghe");
                    break;
                }

                case "reading":
                {
                    _viewModel = new ReadingViewModel();
                    CreateLayoutView("Tập đọc");
                    break;
                }

                case "grammar":
                {
                    _viewModel = new GrammarViewModel();
                    CreateLayoutView("Ngữ pháp");
                    break;
                }

                case "multiplechoice":
                {
                    _viewModel = new MultipleChoiceViewModel();
                    CreateLayoutView("Trắc nghiệm");
                    break;
                }

                default:
                {
                    _viewModel = new LearningViewModel();
                    CreateLayoutView("Tự học");
                    break;
                }
                }
            }
            else
            {
                _viewModel = new LearningViewModel();
                CreateLayoutView("Tự học");
                ViewBag.page = "Index";
                return(View(_viewModel));
            }

            return(View("Index", "~/Views/Layout/_LearningLayout.cshtml", _viewModel));
        }
 public ActionResult WordForm()
 {
     _viewModel = new WordFormViewModel();
     return(PartialView("_WordForm", WordFormViewModel));
 }