public async Task <IActionResult> RenderPreviewExam(Guid?logId, Guid?currentInstructorId)
        {
            if (logId == null || logId == Guid.Empty)
            {
                this.ToastError(L["Can not process your review exam"]);
                return(Redirect("/"));
            }

            var res = await _ExamLogService.GetAsync(logId.Value);

            var model = new ExamRenderViewModel();

            if (res.Success)
            {
                #region Kiểm tra xem có phải là GVHD xem lại hay không
                var isInstructorReview = false;
                if (currentInstructorId != null &&
                    currentInstructorId.Value != Guid.Empty &&
                    currentInstructorId.Value == CurrentUser.Id)
                {
                    isInstructorReview = await ExamCatInstructorRepository.AnyAsync(x => x.UserId == CurrentUser.Id.Value && x.ExamCategoryId == res.Data.ExamCategoryId);
                }
                ViewBag.IsInstructorReview = isInstructorReview;
                #endregion

                model.ExamContent = JsonConvert.DeserializeObject <ExamForRenderDTO>(res.Data.RawExamRendered);
                model.ExamLogId   = res.Data.Id;

                model = await ProcessParams(model);

                var creatorId = await _ExamLogService.GetCreatorId(logId.Value);

                if (creatorId != null && creatorId != Guid.Empty)
                {
                    model.ExamUser = (await _AppUserService.GetAsync(creatorId.Value)).Data;
                }
                ViewBag.Answers = JsonConvert.DeserializeObject <List <QAPairDTO> >(res.Data.UserAnswers);
                ViewBag.Scores  = res.Data.ExamScores.ToString("0.0");

                ViewBag.TimeInMinutes = res.Data.ExamTimeInMinutes;
                ViewBag.IsDoneScore   = res.Data.IsDoneScore;

                ViewBag.ExamLogId = res.Data.Id;

                ViewBag.InstructorComment = res.Data.InstructorComments;

                ViewBag.RenderType = res.Data.RenderExamType;

                return(View(AppTheme.ExamPreview, model));
            }
            else
            {
                this.ToastError(L["Can not process your previous exam"]);
                return(Redirect("/"));
            }
        }