微信小程序服务商下子商户支付下单接口

 <?php
namespace app\index\controller;
class WeixinPay extends Base
{
protected $appid;
protected $mch_id;
protected $key;
protected $openid;
protected $out_trade_no;
protected $body;
protected $total_fee;
function __construct($appid, $openid, $mch_id, $key,$out_trade_no,$body,$total_fee)
{
    $this->appid = $appid;
    $this->openid = $openid;
    $this->mch_id = $mch_id;
    $this->key = $key;
    $this->out_trade_no = $out_trade_no;
    $this->body = $body;
    $this->total_fee = $total_fee;
}
public function pay() {
    //统一下单接口
    $return = $this->weixinapp();
    return $return;
}
//统一下单接口
private function unifiedorder() {
    $url = 'https://api.mch.weixin.qq.com/pay/unifiedorder';
    $parameters = array(
        'appid' =>'', //服务商关联公众号appid
        'sub_appid'=>$this->appid,//子商户小程序appid
        'mch_id' =>'', //服务商商户号
        'nonce_str' => $this->createNoncestr(), //随机字符串
        'sub_mch_id'=>$this->mch_id,//子商户商户号
        'body' => $this->body,//商品描述
        'out_trade_no'=> $this->out_trade_no,//子商户订单号
        'total_fee' => floatval(0.01 * 100), //总金额 单位 分
        // 'total_fee' => $this->total_fee,
        'spbill_create_ip' => $_SERVER['REMOTE_ADDR'], //终端 IP
        'notify_url' => '', //通知地址  确保外网能正常访问
        'sub_openid' => $this->openid, //子商户用户 openid//这里传子商户小程序openid就行了
        'trade_type' => 'JSAPI'//交易类型
    );
    //统一下单签名
    $parameters['sign'] = $this->getSign($parameters);
    $xmlData = $this->arrayToXml($parameters);
    $return = $this->xmlToArray($this->postXmlCurl($xmlData, $url, 60));
    return $return;
}
private static function postXmlCurl($xml, $url, $second = 30)
{
    $ch = curl_init();
    //设置超时
    curl_setopt($ch, CURLOPT_TIMEOUT, $second);
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE); //严格校验
    //设置 header
    curl_setopt($ch, CURLOPT_HEADER, FALSE);
    //要求结果为字符串且输出到屏幕上
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
    //post 提交方式
    curl_setopt($ch, CURLOPT_POST, TRUE);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);
    curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 20);
    curl_setopt($ch, CURLOPT_TIMEOUT, 40);
    set_time_limit(0);
    //运行 curl
    $data = curl_exec($ch);
    //返回结果
    if ($data) {
        curl_close($ch);
        return $data;
    } else {
        $error = curl_errno($ch);
        curl_close($ch);
        throw new WxPayException("curl 出错，错误码:$error");
    }
}

//数组转换成 xml
private function arrayToXml($arr) {
    $xml = "<xml>";
    foreach ($arr as $key => $val) {
        if (is_array($val)) {
            $xml .= "<" . $key . ">" . arrayToXml($val) . "</" . $key . ">";
        } else {
            $xml .= "<" . $key . ">" . $val . "</" . $key . ">";
        }
    }
    $xml .= "</xml>";
    return $xml;
}

//xml 转换成数组
private function xmlToArray($xml) {
    //禁止引用外部 xml 实体
    libxml_disable_entity_loader(true);
    $xmlstring = simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA);
    $val = json_decode(json_encode($xmlstring), true);
    return $val;
}
//微信小程序接口
private function weixinapp() {
    //统一下单接口
    $unifiedorder = $this->unifiedorder();
  // dump($unifiedorder);
    $parameters = array(
        'appId' => $this->appid, //小程序 ID
        'timeStamp' => '' . time() . '', //时间戳
        'nonceStr' => $this->createNoncestr(), //随机串
        'package' => 'prepay_id=' . $unifiedorder['prepay_id'], //数据包
        'signType' => 'MD5'//签名方式
    );
    //签名
    $parameters['paySign'] = $this->getSign($parameters);
    return $parameters;
}
//作用：产生随机字符串，不长于 32 位
private function createNoncestr($length = 32) {
    $chars = "abcdefghijklmnopqrstuvwxyz0123456789";
    $str = "";
    for ($i = 0; $i < $length; $i++) {
        $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
    }
    return $str;
}
//作用：生成签名
private function getSign($Obj) {
    foreach ($Obj as $k => $v) {
        $Parameters[$k] = $v;
    }
    //签名步骤一：按字典序排序参数
    ksort($Parameters);
    $String = $this->formatBizQueryParaMap($Parameters, false);
    //签名步骤二：在 string 后加入 KEY
    $String = $String . "&key=" . $this->key;
    //签名步骤三：MD5 加密
    $String = md5($String);
    //签名步骤四：所有字符转为大写
    $result_ = strtoupper($String);
    return $result_;
}
///作用：格式化参数，签名过程需要使用
private function formatBizQueryParaMap($paraMap, $urlencode) {
    $buff = "";
    ksort($paraMap);
    foreach ($paraMap as $k => $v) {
        if ($urlencode) {
            $v = urlencode($v);
        }
        $buff .= $k . "=" . $v . "&";
    }
    $reqPar = '';
    if (strlen($buff) > 0) {
        $reqPar = substr($buff, 0, strlen($buff) - 1);
    }
    return $reqPar;
}
}

调用方法

  <?php
  namespace app\index\controller;
  use app\admin\model\Applet;
  class Payfee extends Base
{
public function index()
{
    if ($this->request->isPost()) {
        include 'WeixinPay.php';
        $data = $this->request->param();
        $appid = '';
        $openid ='';
        $mch_id = ''; //微信支付商户支付号
        $key = ''; //Api 密钥
        $out_trade_no = $data['ordersn'];
        $total_fee = $data['fee'];
        $body = '商品';
        $weixinpay = new WeixinPay($appid, $openid, $mch_id, $key, $out_trade_no, $body, $total_fee);
        $return = $weixinpay->pay();
        return json_encode(['code'=>40001,'msg'=>'ok','data'=>$return]);
    }
}
}