问使用退款？

EN

<?php

require_once(dirname(__FILE__) . '/paypalSDK/autoload.php'); // require paypal files
require_once(dirname(__FILE__) . '/paypalSDK/paypal/rest-api-sdk-php/sample/common.php'); // require paypal files
// call required stuff
use PayPal\Api\Address;
use PayPal\Api\Amount;
use PayPal\Api\Details;
use PayPal\Api\ExecutePayment;
use PayPal\Api\FundingInstrument;
use PayPal\Api\Item;
use PayPal\Api\ItemList;
use PayPal\Api\Payer;
use PayPal\Api\Payment;
use PayPal\Api\PaymentCard;
use PayPal\Api\PaymentExecution;
use PayPal\Api\Transaction;
use PayPal\Api\Capture;
use PayPal\Api\Refund;
use PayPal\Api\RefundRequest;
use PayPal\Api\Sale;

$orderID = $_GET['order_id']; // order ID we wish to refund
// pull the details from the database so we have the transaction refund ID
$refQ = mysql_query("SELECT * FROM orders WHERE orders_ID = $orderID", $db);
$refC = mysql_num_rows($refQ);
if(!empty($refC)){

    $refR = mysql_fetch_assoc($refQ);
    $refNumber = $refR['orders_transaction_ref']; // paypal transaction ID
    $FinalTotal = $refR['orders_order_total']; // order total
    // paypal credentials
    $apiContext = new \PayPal\Rest\ApiContext(
        new \PayPal\Auth\OAuthTokenCredential(
            'abc',    
            'xyz'  
        )
    );
    $apiContext->setConfig(array('mode' => 'live',)); // live use, not sandbox

    //$amount = new Amount();  // commenting these out seemingly has no effect
    //$amount->setCurrency("USD")  // commenting these out seemingly has no effect
    //    ->setTotal($FinalTotal);  // commenting these out seemingly has no effect

    $refund = new Refund(); // if I comment these 2 lines out, I get "refund cannot be null"
    $refund->setAmount($FinalTotal); // if I comment these 2 lines out, I get "refund cannot be null"

    $sale = new Capture(); // if I comment these 2 lines out, I get "Call to a member function refund() on a non-object"
    $sale->setId($refNumber); // if I comment these 2 lines out, I get "Call to a member function refund() on a non-object"

    $refundRequest = new RefundRequest(); // commenting these out seemingly has no effect
    $refundRequest->setAmount($FinalTotal); // commenting these out seemingly has no effect

    //$captureRefund = $sale->refundCapturedPayment($refundRequest, $apiContext); // failure, error 400

    try {
        $sale->refund($refund, $apiContext);
        //$sale->refundCapturedPayment($refund, $apiContext); // failure, error 400
    } catch (Exception $ex) {
        echo '<pre style="font-size:16px;">';
            var_dump($ex);
        echo '</pre>';
        exit();
        die;
    }
}

object(PayPal\Api\Refund)#3 (1) {
  ["_propMap":"PayPal\Common\PayPalModel":private]=>
  array(5) {
    ["id"]=>
    string(17) "123456789123456789"
    ["create_time"]=>
    string(20) "2017-03-06T20:56:32Z"
    ["state"]=>
    string(9) "completed"
    ["amount"]=>
    object(PayPal\Api\Amount)#9 (1) {
      ["_propMap":"PayPal\Common\PayPalModel":private]=>
      array(3) {
        ["total"]=>
        string(4) "0.02"
        ["currency"]=>
        string(3) "USD"
        ["details"]=>
        object(PayPal\Api\Details)#13 (1) {
          ["_propMap":"PayPal\Common\PayPalModel":private]=>
          array(1) {
            ["subtotal"]=>
            string(4) "0.02"
          }
        }
      }
    }
    ["links"]=>
    array(1) {
      [0]=>
      object(PayPal\Api\Links)#17 (1) {
        ["_propMap":"PayPal\Common\PayPalModel":private]=>
        array(3) {
          ["href"]=>
          string(59) "https://api.paypal.com/v1/payments/refund/123456789123456789"
          ["rel"]=>
          string(4) "self"
          ["method"]=>
          string(3) "GET"
        }
      }
    }
  }
}

require_once(dirname(__FILE__) . '/paypalSDK/autoload.php'); // require paypal files
require_once(dirname(__FILE__) . '/paypalSDK/paypal/rest-api-sdk-php/sample/bootstrap.php'); // require paypal files
require_once(dirname(__FILE__) . '/paypalSDK/paypal/rest-api-sdk-php/sample/common.php'); // require paypal files
// call required stuff
use PayPal\Api\Address;
use PayPal\Api\Amount;
use PayPal\Api\Details;
use PayPal\Api\ExecutePayment;
use PayPal\Api\FundingInstrument;
use PayPal\Api\Item;
use PayPal\Api\ItemList;
use PayPal\Api\Payer;
use PayPal\Api\Payment;
use PayPal\Api\PaymentCard;
use PayPal\Api\PaymentExecution;
use PayPal\Api\Transaction;
use PayPal\Api\Capture;
use PayPal\Api\Refund;
use PayPal\Api\RefundRequest;
use PayPal\Api\Sale;

$orderID = $_GET['order_id']; // internal order ID we wish to refund

// pull the details from database so we have the PayPal transction ID
$refQ = mysql_query("SELECT * FROM orders WHERE orders_ID = $orderID", $db);
$refC = mysql_num_rows($refQ);
if(!empty($refC)){

    $refR = mysql_fetch_assoc($refQ);
    $refNumber = $refR['orders_transaction_ref']; // PayPal transaction ID 

    // attempted 'PAY-' ID, results in "Requested resource ID was not found."
    // $refNumber = $refR['orders_payment_ref']; // ex. PAY-123456789012345678901234 

    $FinalTotal = $refR['orders_order_total']; // order total

    // paypal credentials
    $apiContext = new \PayPal\Rest\ApiContext(
        new \PayPal\Auth\OAuthTokenCredential(
            'abc',    
            'xyz'  
        )
    );
    $apiContext->setConfig(array('mode' => 'live',)); // live use, not sandbox

    //$amount = new Amount();  // commenting these out seemingly has no effect
    //$amount->setCurrency("USD")  // commenting these out seemingly has no effect
    //    ->setTotal($FinalTotal);  // commenting these out seemingly has no effect

    /*
    // attempted code 
    // ### Refund object
    $refund = new Refund();
    //$refund = new RefundRequest();
    $refund->setAmount($FinalTotal);
    */

    $refund = new Refund();
    $refund->setId($refNumber);
    $refund->setSaleId($refNumber);
    $refund->setAmount($FinalTotal);
    $refund->setReason("Testing refund code");
    //$refund->get($refNumber, $apiContext);

    // Attempted code, didn't work
    // https://stackoverflow.com/questions/18927591/paypal-api-how-to-get-sale-id-and-refund-payment-made-via-paypal
    // Fatal error: Uncaught exception 'InvalidArgumentException' with message 'paymentId cannot be null' in /home/cartridgeworkspl/public_html/cfx_controllers/paypalSDK/paypal/rest-api-sdk-php/lib/PayPal/Validation/ArgumentValidator.php:25 Stack trace: #0 
    // $payments = Payment::get($refNumber, $apiContext);
    // $payments->getTransactions();
    // $obj = $payments->toJSON();//I wanted to look into the object
    // $paypal_obj = json_decode($obj);//I wanted to look into the object
    // $transaction_id = $paypal_obj->transactions[0]->related_resources[0]->sale->id;
    // $this->refund($transaction_id);//Call your custom refund method

    try {
        //var_dump($refund);
        $refundResponse = Refund::get($refNumber, $apiContext);
        echo '<pre>';
            var_dump($refundResponse);
        echo '</pre>';
        echo $refundResponse->getState();
        echo $refundResponse->getReasonCode();
    } catch (Exception $ex) {
        // NOTE: PLEASE DO NOT USE RESULTPRINTER CLASS IN YOUR ORIGINAL CODE. FOR SAMPLE ONLY
        ResultPrinter::printError("Get Payment", "Payment", null, null, $ex);
        exit(1);
    }

}