PayPal API退款给样带id无效

Question

我正在尝试使用PayPal API退款。但我得到了以下错误。

 public function paypal_refund() {
        // Set request-specific fields.
        $transactionID = urlencode('2MH09332752606614');
        $refundType = urlencode('Full');  // or 'Partial'
        $amount;                          // required if Partial.
        $memo;                            // required if Partial.
        $currencyID = urlencode('USD');   // or other currency ('GBP', 'EUR', 'JPY', 'CAD', 'AUD')
        // Add request-specific fields to the request string.
        $nvpStr = "&TRANSACTIONID=$transactionID&REFUNDTYPE=$refundType&CURRENCYCODE=$currencyID";
        if (isset($memo)) {
            $nvpStr .= "&NOTE=$memo";
        }
        if (strcasecmp($refundType, 'Partial') == 0) {
            if (!isset($amount)) {
                exit('Partial Refund Amount is not specified.');
            } else {
                $nvpStr = $nvpStr . "&AMT=$amount";
            }
            if (!isset($memo)) {
                exit('Partial Refund Memo is not specified.');
            }
        }
// Execute the API operation; see the PPHttpPost function above.
        $env = 'sandbox';
        $httpParsedResponseAr = $this->PPHttpPost('RefundTransaction', $nvpStr);
        pr($httpParsedResponseAr);
        if ("SUCCESS" == strtoupper($httpParsedResponseAr["ACK"]) || "SUCCESSWITHWARNING" == strtoupper($httpParsedResponseAr["ACK"])) {
            exit('Refund Completed Successfully: ' . print_r($httpParsedResponseAr, true));
        } else {
            exit('RefundTransaction failed: ' . print_r($httpParsedResponseAr, true));
        }
    }
    /**
     * Send HTTP POST Request
     *
     * @param     string     The API method name
     * @param     string     The POST Message fields in &name=value pair format
     * @return     array     Parsed HTTP Response body
     */
    public function PPHttpPost($methodName_, $nvpStr_) {
        // Set up your API credentials, PayPal end point, and API version.
        $API_UserName = urlencode('myusername');
        $API_Password = urlencode('mypassword');
        $API_Signature = urlencode('mysignature');
        $API_Endpoint = "https://api-3t.paypal.com/nvp";
        $environment = 'sandbox';
        if ("sandbox" === $environment || "beta-sandbox" === $environment) {
            $API_Endpoint = "https://api-3t.$environment.paypal.com/nvp";
        }
        $version = urlencode('51.0');
        // Set the curl parameters.
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $API_Endpoint);
        curl_setopt($ch, CURLOPT_VERBOSE, 1);
        // Turn off the server and peer verification (TrustManager Concept).
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        // Set the API operation, version, and API signature in the request.
        $nvpreq = "METHOD=$methodName_&VERSION=$version&PWD=$API_Password&USER=$API_UserName&SIGNATURE=$API_Signature$nvpStr_";
        // Set the request as a POST FIELD for curl.
        curl_setopt($ch, CURLOPT_POSTFIELDS, $nvpreq);
        // Get response from the server.
        $httpResponse = curl_exec($ch);
        if (!$httpResponse) {
            exit("$methodName_ failed: " . curl_error($ch) . '(' . curl_errno($ch) . ')');
        }
        // Extract the response details.
        $httpResponseAr = explode("&", $httpResponse);
        $httpParsedResponseAr = array();
        foreach ($httpResponseAr as $i => $value) {
            $tmpAr = explode("=", $value);
            if (sizeof($tmpAr) > 1) {
                $httpParsedResponseAr[$tmpAr[0]] = $tmpAr[1];
            }
        }
        if ((0 == sizeof($httpParsedResponseAr)) || !array_key_exists('ACK', $httpParsedResponseAr)) {
            exit("Invalid HTTP Response for POST request($nvpreq) to $API_Endpoint.");
        }
        return $httpParsedResponseAr;
    }

错误：

Array
(
    [TIMESTAMP] => 2015%2d10%2d29T10%3a18%3a16Z
    [CORRELATIONID] => e2b916cdb99d6
    [ACK] => Failure
    [VERSION] => 51%2e0
    [BUILD] => 18308778
    [L_ERRORCODE0] => 10004
    [L_SHORTMESSAGE0] => Transaction%20refused%20because%20of%20an%20invalid%20argument%2e%20See%20additional%20error%20messages%20for%20details%2e
    [L_LONGMESSAGE0] => The%20transaction%20id%20is%20not%20valid
    [L_SEVERITYCODE0] => Error
)
RefundTransaction failed: Array ( [TIMESTAMP] => 2015%2d10%2d29T10%3a18%3a16Z [CORRELATIONID] => e2b916cdb99d6 [ACK] => Failure [VERSION] => 51%2e0 [BUILD] => 18308778 [L_ERRORCODE0] => 10004 [L_SHORTMESSAGE0] => Transaction%20refused%20because%20of%20an%20invalid%20argument%2e%20See%20additional%20error%20messages%20for%20details%2e [L_LONGMESSAGE0] => The%20transaction%20id%20is%20not%20valid [L_SEVERITYCODE0] => Error ) 

Answer 1

2MH09332752606614不是PayPal交易id。请参阅https://en.support.wordpress.com/paypal-transaction-id/，登录sandbox.paypal.com，在帐户历史页面中获取有效的交易id。