public void PostOldStudent(Student student)
        {
            SystemContext context    = HttpContext.RequestServices.GetService(typeof(Exam_Management_System.Models.SystemContext)) as SystemContext;
            int           academic   = context.GetAcademicSecond().Id;
            int           student_id = context.GetStudentId(student.Rollno, academic);
            int           mark       = context.GetMark(student_id);

            using (MySqlConnection conn = context.GetConnection())
            {
                conn.Open();
                string sql1 = $"Insert Into old_student (student_year_id,address,phone,father_phone,mother_phone,email,academic_id,major_id,student_id,mark) Values ('{student.Year_id}','{student.Address}','{student.Phone}','{student.Father_phone}','{student.Mother_phone}','{student.Email}','{student.Academic_id}','{student.Major_id}','{student_id}','{mark}')";
                using (MySqlCommand command1 = new MySqlCommand(sql1, conn))
                {
                    command1.ExecuteNonQuery();
                }
            }
            // return Redirect("/Student/AddOldStudent");
        }