.net 如何从realex payment的HPP post响应中获取请求[“产品ID”]

我已经使用controller发布了RealexPaymentRedirectRequest 我使用控制器重定向请求post到realex支付

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。 我已使用请求[PROD_ID]尝试从HPP响应请求，

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但这返回的是空字符串。

实际上不是RealexPaymentRedirectRequest的专家，但您要查找的值是否可以隐藏在另一个表单集合键中？来自HPP post的响应包含这些字段。我需要prod_id从HPP response post返回