/**
   * 微信支付接口
   */
  wxPaymoney:function (out_trade_no, true_money){    //out_trade_no 后台统一下单接口需要用
    var that = this
    wx.hideToast()                   //隐藏toast
    wx.request({
      method: \'POST\',
      data: {
        openid: \'************\',    //调用人的openid
        out_trade_no: out_trade_no,
        body: \'答题奖金\',  
        no****rl: \'https://www.q**************.php\',//后台接口自动修改订单状态
        t*****e: true_money     //支付金额
      },
      url: \'https://b***************gn.php\',        //服务器接口（微信统一下单接口）
      header: {
        \'Content-Type\': \'application/x-www-form-urlencoded\'
      },
      success: function (res) {
        console.log(res.data)
        console.log(\'调起支付\')
        wx.requestPayment({                //成功之后，调用小程序微信支付
          \'timeStamp\': res.data.timeStamp,
          \'nonceStr\': res.data.nonceStr,
          \'package\': res.data.package,
          \'signType\': \'MD5\',
          \'paySign\': res.data.paySign,
          success: function (res) {
            console.log(res)
            wx.showToast({
              title: \'支付成功\',
              icon: \'success\',
              duration: 3000
            })
          }, 
          fail: function (res) {
            console.log(\'付款失败\');
            wx.showModal({
              title: \'提醒\',
              content: \'付款失败,如要出题请重新编辑题目\',
              showCancel: false,
              success:function(){
                wx.redirectTo({
                  url: \'/pa*******ndex\',
                })
              }
            })
            return
          },
        })
      },
      fail: function (res) {
        console.log(res.data)
      }
    })
  }

<?php
$appid=\'********\';        //准备数据（都在后台系统中可查到）
$mch_id=\'12******02\';        //商户号
$key=\'lk******aFK12\';
$openid = trim($_POST[\'openid\']);
//$out_trade_no = $mch_id.time();
$out_trade_no = trim($_POST[\'out_trade_no\']);
//$body = "答题奖金";
$body = $_POST[\'body\'];
//$notify_url = \'http://w***************y.php\';
$notify_url = trim($_POST[\'notify_url\']);
$to**ee = floatval($_POST[\'to****e\']);
$str = var_export($_POST,true);
file_put_contents("set.txt",$str."\n",FILE_APPEND);
 
$weixinpay = new WeixinPay($appid,$openid,$mch_id,$key,$out_trade_no,$body,$to****,$notify_url);
$return=$weixinpay->pay();
echo json_encode($return);
/*
 * 小程序微信支付
 */
class WeixinPay {
    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,$notify_url) {
        $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;
        $this->notify_url = $notify_url;
    }
    public function pay() {
        //统一下单接口
        $return = $this->weixinapp();
        return $return;
    }
    //微信小程序接口
    private function weixinapp() {
        //统一下单接口
        $unifiedorder = $this->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;
    }
    //统一下单接口
    private function unifiedorder() {
        $url = \'https://api.mch.weixin.qq.com/pay/unifiedorder\';
        $parameters = array(
            \'appid\' => $this->appid, //小程序ID
            \'mch_id\' => $this->mch_id, //商户号
            \'nonce_str\' => $this->createNoncestr(), //随机字符串
            \'body\' => $this->body,
            \'out_trade_no\'=> $this->out_trade_no,
            \'total_fee\' => $this->t***ee,
            \'spbill_create_ip\' => \'1****8\', //终端IP
            \'notify_url\' => $this->notify_url, //通知地址  确保外网能正常访问
            \'openid\' => $this->openid, //用户id
            \'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) {
        $xml = "<root>";
        foreach ($arr as $key => $val) {
            if (is_array($val)) {
                $xml .= "<" . $key . ">" . arrayToXml($val) . "</" . $key . ">";
            } else {
                $xml .= "<" . $key . ">" . $val . "</" . $key . ">";
            }
        }
        $xml .= "</root>";
        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 $val;
    }
    //作用：产生随机字符串，不长于32位
    private function createNoncestr($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;
    }
}
?>