* As such, we need to loop through all the payment info in the response.
     *
     * The library helps us do this using the GetExpressCheckoutPaymentInfo() method.  We'll
     * load our $payments_info using that method, and then loop through the results to pull
     * out our details for the transaction.
     *
     * Again, in this case we are you only working with a single payment, but we'll still
     * loop through the results accordingly.
     *
     * Here, we're only pulling out the PayPal transaction ID and fee amount, but you may
     * refer to the API reference for all the additional parameters you have available at
     * this point.
     *
     * https://developer.paypal.com/docs/classic/api/merchant/DoExpressCheckoutPayment_API_Operation_NVP/
     */
    $payments_info = $PayPal->GetExpressCheckoutPaymentInfo($PayPalResult);
    foreach ($payments_info as $payment_info) {
        $_SESSION['paypal_transaction_id'] = isset($payment_info['TRANSACTIONID']) ? $payment_info['TRANSACTIONID'] : '';
        $_SESSION['paypal_fee'] = isset($payment_info['FEEAMT']) ? $payment_info['FEEAMT'] : '';
    }
} else {
    $_SESSION['paypal_errors'] = $PayPalResult['ERRORS'];
    header('Location: /demo/error.php');
    exit;
}
/**
 * Here we're simply generating a very basic result page that
 * will display a popup message notifying the user whether
 * the payment was successful or not, and will then close
 * the payment window, leaving the user right back where they
 * were prior to starting payment.