如何在PayPal的快速​​结账中设置'到电子邮件地址'？

Question

设置： 我有一个paypal商业帐户，主要电子邮件和几个辅助或备用电子邮件。 我可以将自适应付款配置为转到特定的备用电子邮件，从而区分付款的来源。

问题： 使用“SetExpressCheckout”和“DoExpressCheckoutPayment”API调用开发快速结账付款我遇到了无法明确设置'到电子邮件地址'的问题，所有付款最终都显示为主要的PayPal电子邮件地址。

Some suggest using the "SUBJECT" query parameter，但它似乎不起作用。

是否可以指定快速付款应转到哪个电子邮件地址，如果是，如何？

以下是控制将哪些查询参数传递给“SetExpressCheckout”的Ruby代码：

public boolean checkMobileInternetConn() {
        //Create object for ConnectivityManager class which returns network related info
        ConnectivityManager connectivity = (ConnectivityManager) _context
                .getSystemService(Context.CONNECTIVITY_SERVICE);
        //If connectivity object is not null
        if (connectivity != null) {
            //Get network info - WIFI internet access
            NetworkInfo info = connectivity.getNetworkInfo(ConnectivityManager.TYPE_WIFI);

            if (info != null) {
                //Look for whether device is currently connected to WIFI network
                if (info.isConnected()) {
                    return true;
                }
            }
        }
        return false;
    }

和“DoExpressCheckoutPayment：

hash = {
    "USER" => user_id,
    "PWD" => password,
    "SIGNATURE" => signature,
    "METHOD" => "SetExpressCheckout",
    "RETURNURL" => options[:return_url], # URL of your payment confirmation page
    "CANCELURL" => options[:cancel_url], # URL redirect if customer cancels payment
    "VERSION" => 124, # this may increase in the future
    "SOLUTIONTYPE" => "Sole",
    "LANDINGPAGE" => "Billing",
    "EMAIL" => options[:email],
    "PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID" => options[:receiver_email], # explictly set what paypal account will recieve the payment
    "PAYMENTREQUEST_0_PAYMENTACTION" => "SALE",
    "PAYMENTREQUEST_0_AMT" => options[:receiver_amount],
    "PAYMENTREQUEST_0_CURRENCYCODE" => options[:currency_code],
    "SUBJECT" => options[:receiver_email]
}

请注意，我会在每个机会将“PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID”参数设置为其中一个替代的PayPal帐户电子邮件。