PHP实现微信退款的分析与源码实现

<?php
/**
 * 关于微信退款的说明
 * 1.微信退款要求必传证书，需要到https://pay.weixin.qq.com 账户中心->账户设置->API安全->下载证书，证书路径在第119行和122行修改
 * 2.错误码参照 ：https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=9_4
 */
header('Content-type:text/html; Charset=utf-8');
$mchid = 'xxxxx';          //微信支付商户号 PartnerID 通过微信支付商户资料审核后邮件发送
$appid = 'xxxxx';  //微信支付申请对应的公众号的APPID
$apiKey = 'xxxxx';   //https://pay.weixin.qq.com 帐户设置-安全设置-API安全-API密钥-设置API密钥
$orderNo = '';                      //商户订单号（商户订单号与微信订单号二选一，至少填一个）
$wxOrderNo = '';                     //微信订单号（商户订单号与微信订单号二选一，至少填一个）
$totalFee = 0.01;                   //订单金额，单位:元
$refundFee = 0.01;                  //退款金额，单位:元
$refundNo = 'refund_'.uniqid();        //退款订单号(可随机生成)
$wxPay = new WxpayService($mchid,$appid,$apiKey);
$result = $wxPay->doRefund($totalFee, $refundFee, $refundNo, $wxOrderNo,$orderNo);
if($result===true){
    echo 'refund success';exit();
}
echo 'refund fail';

?>

<?php class WxpayService { protected $mchid; protected $appid; protected $apiKey; public $data = null; public function __construct($mchid, $appid, $key) { $this->mchid = $mchid; //https://pay.weixin.qq.com 产品中心-开发配置-商户号 $this->appid = $appid; //微信支付申请对应的公众号的APPID $this->apiKey = $key; //https://pay.weixin.qq.com 帐户设置-安全设置-API安全-API密钥-设置API密钥  } /** * 退款 * @param float $totalFee 订单金额 单位元 * @param float $refundFee 退款金额 单位元 * @param string $refundNo 退款单号 * @param string $wxOrderNo 微信订单号 * @param string $orderNo 商户订单号 * @return string */ public function doRefund($totalFee, $refundFee, $refundNo, $wxOrderNo='',$orderNo='') { $config = array( 'mch_id' => $this->mchid, 'appid' => $this->appid, 'key' => $this->apiKey, ); $unified = array( 'appid' => $config['appid'], 'mch_id' => $config['mch_id'], 'nonce_str' => self::createNonceStr(), 'total_fee' => intval($totalFee * 100), //订单金额 单位 转为分 'refund_fee' => intval($refundFee * 100), //退款金额 单位 转为分 'sign_type' => 'MD5', //签名类型 支持HMAC-SHA256和MD5，默认为MD5 'transaction_id'=>$wxOrderNo, //微信订单号 'out_trade_no'=>$orderNo, //商户订单号 'out_refund_no'=>$refundNo, //商户退款单号 'refund_desc'=>'商品已售完', //退款原因（选填）  ); $unified['sign'] = self::getSign($unified, $config['key']); $responseXml = $this->curlPost('https://api.mch.weixin.qq.com/secapi/pay/refund', self::arrayToXml($unified)); $unifiedOrder = simplexml_load_string($responseXml, 'SimpleXMLElement', LIBXML_NOCDATA); if ($unifiedOrder === false) { die('parse xml error'); } if ($unifiedOrder->return_code != 'SUCCESS') { die($unifiedOrder->return_msg); } if ($unifiedOrder->result_code != 'SUCCESS') { die($unifiedOrder->err_code); } return true; } public static function curlGet($url = '', $options = array()) { $ch = curl_init($url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_TIMEOUT, 30); if (!empty($options)) { curl_setopt_array($ch, $options); } //https请求 不验证证书和host curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false); $data = curl_exec($ch); curl_close($ch); return $data; } public function curlPost($url = '', $postData = '', $options = array()) { if (is_array($postData)) { $postData = http_build_query($postData); } $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, $postData); curl_setopt($ch, CURLOPT_TIMEOUT, 30); //设置cURL允许执行的最长秒数 if (!empty($options)) { curl_setopt_array($ch, $options); } //https请求 不验证证书和host curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false); //第一种方法，cert 与 key 分别属于两个.pem文件 //默认格式为PEM，可以注释 curl_setopt($ch,CURLOPT_SSLCERTTYPE,'PEM'); curl_setopt($ch,CURLOPT_SSLCERT,getcwd().'/cert/apiclient_cert.pem'); //默认格式为PEM，可以注释 curl_setopt($ch,CURLOPT_SSLKEYTYPE,'PEM'); curl_setopt($ch,CURLOPT_SSLKEY,getcwd().'/cert/apiclient_key.pem'); //第二种方式，两个文件合成一个.pem文件 // curl_setopt($ch,CURLOPT_SSLCERT,getcwd().'/all.pem'); $data = curl_exec($ch); curl_close($ch); return $data; } public static function createNonceStr($length = 16) { $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'; $str = ''; for ($i = 0; $i < $length; $i++) { $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1); } return $str; } public static function arrayToXml($arr) { $xml = "<xml>"; foreach ($arr as $key => $val) { if (is_numeric($val)) { $xml .= "<" . $key . ">" . $val . "</" . $key . ">"; } else $xml .= "<" . $key . "><![CDATA[" . $val . "]]></" . $key . ">"; } $xml .= "</xml>"; return $xml; } public static function getSign($params, $key) { ksort($params, SORT_STRING); $unSignParaString = self::formatQueryParaMap($params, false); $signStr = strtoupper(md5($unSignParaString . "&key=" . $key)); return $signStr; } protected static function formatQueryParaMap($paraMap, $urlEncode = false) { $buff = ""; ksort($paraMap); foreach ($paraMap as $k => $v) { if (null != $v && "null" != $v) { if ($urlEncode) { $v = urlencode($v); } $buff .= $k . "=" . $v . "&"; } } $reqPar = ''; if (strlen($buff) > 0) { $reqPar = substr($buff, 0, strlen($buff) - 1); } return $reqPar; } } ?>