public ActionResult Index(ReturnBookModel model)
        {
            var loanList = DBManager.Instance.GetCurrentStudentBookLoansByStudentReg(model.StudentReg);
            ViewData["LoanList"] = loanList;

            return View(model);
        }
 //
 // GET: /ReturnBook/
 public ActionResult Index()
 {
     var model = new ReturnBookModel();
     return View(model);
 }