public async Task <FileResult> ExportStudent(Guid examPeriodId, Guid examRoomId)
        {
            ExamRoomExamPeriodFilter filter = new ExamRoomExamPeriodFilter
            {
                ExamPeriodId = new GuidFilter {
                    Equal = examPeriodId
                },
                ExamRoomId = new GuidFilter {
                    Equal = examRoomId
                }
            };

            byte[] data = await ExamRoomExamPeriodService.ExportStudent(filter);

            return(File(data, "application/octet-stream", "Exam.xlsx"));
        }