public ActionResult ChangePassword(string oldpass, string newpass)
        {
            string id       = Session["rollno"].ToString();
            string newpass1 = HttpUtility.HtmlEncode(newpass);
            string oldpass1 = HttpUtility.HtmlEncode(oldpass);

            string getPasswordChangeResult = studentModel.ChangePassword_StudentModelFunction(oldpass1, newpass1, id);

            ViewBag.Message = getPasswordChangeResult;
            return(View());
        }