public IActionResult AssignMark(ExamMark examMark)
 {
     try
     {
         int Logged = Convert.ToInt32(HttpContext.Session.GetInt32("Logged"));
         int User   = Convert.ToInt32(HttpContext.Session.GetInt32("User"));
         if (Logged == 1 && User == 2)
         {
             examMark.Calculate();
             teacherDA.UpdateMark(examMark);
             string success = "Marks entered successfully";
             return(RedirectToAction("StudentList", new { message = success }));
         }
         else
         {
             return(RedirectToAction("Login", "Home"));
         }
     }
     catch (Exception ex)
     {
         string exMessage = "oops! There is a problem in assigning marks.";
         return(RedirectToAction("Index", "ExeptionHandler", new { Exeption = exMessage }));
     }
 }