.net - 如何从 realex 支付的 HPP 发布响应中获取请求 [“PROD_ID”]

Question

我已经使用控制器向 RealexPaymentRedirectRequest 发布了一个帖子，我使用控制器重定向请求发布到 realex 付款。

RedirectRequest postData = new RealexPaymentRedirectRequest()
                                        {
                                            Account = Sitecore.Configuration.Settings.GetSetting("realexaccount", "internet"),
                                            AutoSettleFlag = "1",
                                            Currency = "GBP",
                                            MerchantId = Sitecore.Configuration.Settings.GetSetting("realexmerchant", "merchant"),
                                            MerchantResponseUrl = Sitecore.Configuration.Settings.GetSetting("realexmerchantResponseUrl", "http://www.mydomainhost.uk/service/CompletePayment.ashx"),
                                            OrderId = orderId,
                                            Timestamp = RealexPaymentRedirectRequest.GenerateTimestamp(),
                                            Secret = Sitecore.Configuration.Settings.GetSetting("realexsecret", "topsceret"),

                                            Vat = vatRate != 0 ? vatRate : Sitecore.Configuration.Settings.GetIntSetting("realexdefaultVatRate", 20),
                                            Amount = amountToPay,
                                            ProdId = prodId
                                        };

我想将 prod id 字符串返回到我的确认页面。我已经尝试使用 request[PROD_ID] 从 HPP 响应请求中进行尝试，但这会返回空字符串。