微信小程序 --- 完成小程序支付功能

最近开发小程序，一直在看小程序的支付。经过一天的努力，小程序支付功能最终实现了。

下面感谢 csdn 博主：千堆雪惹尘埃 发布的 " 小程序与php 实现微信支付 "

原文地址：

http://blog.csdn.net/admin1008611/article/details/73240458

下面是我自己写的代码：使用的 thinkphp：其他的可以参考修改：

服务端：

获取用户的 openid：

public function get_openid(){
    $data = array();
    $url = "https://api.weixin.qq.com/sns/jscode2session";
    $data['appid'] = I('get.appid','','trim'); // 小程序的app_id
    $data['secret'] = I('get.secret','','trim'); //小程序的 app_secret
    $data['js_code'] = I('get.js_code','','trim');
    $data['grant_type'] = "authorization_code";
    $res = $this->http_request($url,$data);
    echo $res;
}

支付接口：

public function wxPay(){
    $openID = I('get.openid','','trim');
    $totalFee = I('get.total_fee','','trim');
    $title = I('get.title','','trim');
    // 具体配置
    $appid = "填写小程序的 appid"; //小程序 appid
    $openid = $openID; // 用户的openid
    $mch_id = "填写商户号"; //商户号
    $key = "填写商户号的秘钥";
    $out_trade_no = $this->order_number();//商户订单号
    $body = $title;
    $total_fee = $totalFee;//总金额 单位 分
    $weixinpay = new \Components\WeixinPay($appid,$openid,$mch_id,$key,$out_trade_no,$body,$total_fee);
    $result = $weixinpay->pay();
    echo json_encode($result);
}

生成随机字符串和订单号：

//随机32位字符串
private function nonce_str(){
    $result = '';
    $str = 'QWERTYUIOPASDFGHJKLZXVBNMqwertyuioplkjhgfdsamnbvcxz';
    for ($i=0;$i<32;$i++){
        $result .= $str[rand(0,48)];
    }
    return $result;
}
//生成订单号
private function order_number($openid){
    //date('Ymd',time()).time().rand(10,99);//18位
    return md5($openid.time().rand(10,99));//32位
}

支付回调接口：

// 支付回调地址
public function notify(){
    $postXml = $GLOBALS["HTTP_RAW_POST_DATA"]; //接收微信参数
    if (empty($postXml)) {
        return false;
    }  

    //将xml格式转换成数组
    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;
    }  

    $attr = xmlToArray($postXml);  

    $total_fee = $attr[total_fee];
    $open_id = $attr[openid];
    $out_trade_no = $attr[out_trade_no];
    $time = $attr[time_end];
}

小程序JS：

//index.js
//获取应用实例
const app = getApp()
const APP_ID = "小程序的appid";//输入小程序的appid
const APP_SECRET = "小程序的app_secret";//输入小程序app_secret
var OPEN_ID = "";//储存获取到openid
var SESSION_KEY = "";//储存获取到session_key
Page({
  data:{
    'message':"发起支付"
  },
  wxPay:function(){
    var that = this;
    wx.login({
      success:function(res){
        wx.request({
          url:"https://xiaochengxu.e0yu.com/index.php?s=Index/get_openid",
          data:{
            appid: APP_ID,
            secret:APP_SECRET,
            js_code:res.code,
            grant_type: 'authorization_code'
          },
          method:'GET',
          success:function(res){
            //console.log(res);
            OPEN_ID = res.data.openid;//获取到的openid
            wx.request({
              url: "https://xiaochengxu.e0yu.com/index.php?s=Index/wxPay",
              data:{
                openid:OPEN_ID,
                total_fee:1,//充值金额 单位"分"
                title:'商品标题'
              },
              method:'GET',
              success:function(result){
                //console.log(result);
                console.log('调起支付');
                wx.requestPayment({
                  'timeStamp': result.data.timeStamp,
                  'nonceStr': result.data.nonceStr,
                  'package': result.data.package,
                  'signType': 'MD5',
                  'paySign': result.data.paySign,
                  'success': function (res) {
                    console.log('success');
                  },
                  'fail': function (res) {
                    console.log('fail');
                  },
                  'complete': function (res) {
                    console.log('complete');
                  }
                });
              }
            })
          },
        })
      }
    });
  }
})

效果 ：

下面给出：WeixinPay：

<?php
namespace Components;
/* 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) {
        $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' => $this->appid, //小程序ID
            'mch_id' => $this->mch_id, //商户号
            'nonce_str' => $this->createNoncestr(), //随机字符串
//            'body' => 'test', //商品描述
            'body' => $this->body,
//            'out_trade_no' => '2015450806125348', //商户订单号
            'out_trade_no'=> $this->out_trade_no,
//            '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
            'spbill_create_ip' => '192.168.0.161', //终端IP
            'notify_url' => 'http://www.weixin.qq.com/wxpay/pay.php', //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;
    }

    //微信小程序接口
    private function weixinapp() {
        //统一下单接口
        $unifiedorder = $this->unifiedorder();
//        print_r($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;
    }

}