Braintree托管字段解决方案中的未捕获错误

Question

我正在实施一个托管的Braintree解决方案，并且我非常准确地关注这些文档。我必须说文档非常棒。仍然，在加载客户端时仍然收到未捕获的参考错误。错误出现在客户端令牌上。即使已设置，在此我也遇到未捕获的参考错误。

这是出现问题的剃须刀页面的结尾：

     var form = document.querySelector('#my-sample-form');
     var submit = document.querySelector('input[type="submit"]');
     var clientToken = @ViewBag.ClientToken;

        braintree.client.create({
            authorization: clientToken
        }, function (err, clientInstance) {
            if (err) {
                console.error(err);
                return;
            }

这是控制器中的方法（即使我认为不是问题所在）。从获取帐单信息的后方法重定向：

            return RedirectToAction(nameof(Pay));

        }
        else
        {
            return View(order);
        }
    }

    public ActionResult Pay()
    {
        var gateway = GetGetAway();
        string clientToken = gateway.ClientToken.Generate();
        ViewBag.ClientToken = clientToken;

        return View(); 
    }


    public BraintreeGateway GetGetAway()
    {
        return new BraintreeGateway
        {
            Environment = Braintree.Environment.SANDBOX,
            MerchantId = "xxxxxxx",
            PublicKey = "xxxxxxxx",
            PrivateKey = "xxxxxxxxxx"
    };
    }


    [HttpPost]
    public ActionResult CreatePurchase()
    {

            var gateway = config.GetGateway();


            var request = new TransactionRequest
            {
                Amount = 15,
                PaymentMethodNonce = Request.Query["payment_method_nonce"],
                Options = new TransactionOptionsRequest
                {
                    SubmitForSettlement = true
                }
            };


            Result<Transaction> result = gateway.Transaction.Sale(request);
            if (result.IsSuccess())
            {
                Transaction transaction = result.Target;
                return View("Completed");
            }
            else 
            {
                return RedirectToAction("Unsuccessful");
            }

    }