Teach you to use PHP development to implement WeChat refund function

function Home_index() {
 
date_default_timezone_set("Asia/Shanghai");
 
$date = date("YmdHis");
 
$appid = "";
 
$mch_id = "";
 
$out_trade_no = "14487658021497944120";
 
$op_user_id = "";
 
$out_refund_no = $date;
 
$total_fee = "500";
 
$refund_fee = "500";
 
// $transaction_id = "4009542001201706206596667604";
 
$key = "";
 
$nonce_str = nonceStr();
 
$ref = strtoupper(md5("appid=$appid&mch_id=$mch_id&nonce_str=$nonce_str&op_user_id=$op_user_id"
 
. "&out_refund_no=$out_refund_no&out_trade_no=$out_trade_no&refund_fee=$refund_fee&total_fee=$total_fee"
 
. "&key=$key")); //sign加密MD5
 
$refund = array(
 
'appid' =>$appid, //应用ID，固定
 
'mch_id' => $mch_id, //商户号，固定
 
'nonce_str' => $nonce_str, //随机字符串
 
'op_user_id' => $op_user_id, //操作员
 
'out_refund_no' => $out_refund_no, //商户内部唯一退款单号
 
'out_trade_no' => $out_trade_no, //商户订单号,pay_sn码 1.1二选一,微信生成的订单号，在支付通知中有返回
 
// 'transaction_id'=>'1',//微信订单号 1.2二选一,商户侧传给微信的订单号
 
'refund_fee' => $refund_fee, //退款金额
 
'total_fee' => $total_fee, //总金额
 
'sign' => $ref//签名
 
);
 
$url = "https://api.mch.weixin.qq.com/secapi/pay/refund";
 
; //微信退款地址，post请求
 
$xml = arrayToXml($refund);
 
$ch = curl_init();
 
curl_setopt($ch, CURLOPT_URL, $url);
 
curl_setopt($ch, CURLOPT_HEADER, 1);
 
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
 
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1); //证书检查
 
if ($useCert == true) {
 
// 设置证书
 
curl_setopt($ch, CURLOPT_SSLCERTTYPE, 'pem');
 
curl_setopt($ch, CURLOPT_SSLCERT, dirname(__FILE__) . '/WxPay/cert/apiclient_cert.pem');
 
curl_setopt($ch, CURLOPT_SSLCERTTYPE, 'pem');
 
curl_setopt($ch, CURLOPT_SSLKEY, dirname(__FILE__) . '/WxPay/cert/apiclient_key.pem');
 
curl_setopt($ch, CURLOPT_SSLCERTTYPE, 'pem');
 
curl_setopt($ch, CURLOPT_CAINFO, dirname(__FILE__) . '/WxPay/cert/rootca.pem');
 
}
 
curl_setopt($ch, CURLOPT_POST, 1);
 
curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);
 
$xml = curl_exec($ch);
 
// 返回结果0的时候能只能表明程序是正常返回不一定说明退款成功而已
 
if ($xml) {
 
curl_close($ch);
 
// 把xml转化成数组
 
libxml_disable_entity_loader(true);
 
$xmlstring = simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA);
 
// var_dump($xmlstring);
 
$result['errNum'] = 0;
 
$result['info'] = object_to_array($xmlstring);
 
// var_dump($result);
 
return $result;
 
} else {
 
$error = curl_errno($ch);
 
curl_close($ch);
 
// 错误的时候返回错误码。
 
$result['errNum'] = $error;
 
return $result;
 
}
 
}
 
function arrayToXml($arr) {
 
$xml = "";
 
foreach ($arr as $key => $val) {
 
if (is_array($val)) {
 
$xml .= "<" . $key . ">" . arrayToXml($val) . "{C}<!--" ? . $key-->";
 
} else {
 
$xml .= "<" . $key . ">" . $val . "{C}<!--" ? . $key-->";
 
}
 
}
 
$xml .= "";
 
return $xml;
 
}
 
function object_to_array($obj) {
 
$obj = (array) $obj;
 
foreach ($obj as $k => $v) {
 
if (gettype($v) == &#39;resource&#39;) {
 
return;
 
}
 
if (gettype($v) == &#39;object&#39; || gettype($v) == &#39;array&#39;) {
 
$obj[$k] = (array) object_to_array($v);
 
}
 
}
 
return $obj;
 
}
 
function nonceStr() {
 
$chars = "abcdefghijklmnopqrstuvwxyz0123456789";
 
$str = "";
 
$length = 32;
 
for ($i = 0; $i < $length; $i++) {
 
$str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
 
}
 
// 随机字符串
 
return $str;
 
}
 
Home_index();