public void TestXoa()
        {
            var db         = new CsK23T2aEntities1();
            var controller = new Admin_CapNhat_Xoa_TraLoiController();

            using (var scope = new TransactionScope())
            {
                var result = controller.Xoa(2);
                Assert.IsInstanceOfType(result, typeof(HttpNotFoundResult));

                var model = db.Contacts.AsNoTracking().First();
                result = controller.Xoa(model.idContact);
                var redirect = result as RedirectToRouteResult;
                Assert.IsNotNull(redirect);
                Assert.AreEqual("Index", redirect.RouteValues["action"]);
                var item = db.Contacts.Find(model.idContact);
                Assert.IsNull(item);
            }
        }