(统一收单交易退款接口)
$aop = new AopClient ();
$aop->gatewayUrl = '/';
$aop->appId = 'your app_id';
$aop->rsaPrivateKey = '请填写开发者私钥去头去尾去回车，一行字符串';
$aop->alipayrsaPublicKey='请填写支付宝公钥，一行字符串';
$aop->apiVersion = '1.0';
$aop->signType = 'RSA2';
$aop->postCharset='GBK';
$aop->format='json';
$request = new AlipayTradeRefundRequest ();
$request->setBizContent("{" .
"\"out_trade_no\":\"20150320010101001\"," .
"\"trade_no\":\"2014112611001004680073956707\"," .
"\"refund_amount\":200.12," .
"\"refund_currency\":\"USD\"," .
"\"refund_reason\":\"正常退款\"," .
"\"out_request_no\":\"HZ01RF001\"," .
"\"operator_id\":\"OP001\"," .
"\"store_id\":\"NJ_S_001\"," .
"\"terminal_id\":\"NJ_T_001\"," .
" \"goods_detail\":[{" .
" \"goods_id\":\"apple-01\"," .
"\"alipay_goods_id\":\"20010001\"," .
"\"goods_name\":\"ipad\"," .
"\"quantity\":1," .
"\"price\":2000," .
"\"goods_category\":\"34543238\"," .
"\"body\":\"特价手机\"," .
"\"show_url\":\"/\"" .
" }]" .
" }");
$result = $aop->execute ( $request);
$responseNode = str_replace(".", "_", $request->getApiMethodName()) . "_response";
$resultCode = $result->$responseNode->code;
if(!empty($resultCode)&&$resultCode == 10000){
echo "成功";
} else {
echo "失败";
}