public ActionResult ChangePassword(ChangePasswordModel model)
        {
            if (ModelState.IsValid)
            {
                if (_memberService.ChangePassword(User.Identity.Name, model.OldPassword, model.NewPassword))
                {
                    return RedirectToAction("ChangePasswordSuccess");
                }
                else
                {
                    ModelState.AddModelError("", "The current password is incorrect or the new password is invalid.");
                }
            }

            return View(model);
        }