Detailed explanation of implementing WeChat scan code payment function with PHP

/**

 * 微信支付请求接口(POST)

 * @param string $goods_id  商品ID

 * @param string $body      商品简单描述

 * @param string $order_sn  订单编号

 * @param string $total_fee 金额

 * @return  json的数据

 */

public function wxpay($goods_id,$total_fee,$body,$order_sn){

    $config = $this->config;

    //统一下单参数构造

    $unifiedorder = array(

        'appid'         => $config['appid'],

        'mch_id'        => $config['mch_id'],

        'device_info'   => 'WEB',

        'nonce_str'     => self::getNonceStr(),

        'body'          => $body,

        'out_trade_no'  => $order_sn,

        'total_fee'     => $total_fee * 100,

        'spbill_create_ip'  => self::getip(),

        'notify_url'    => 'http://'.$_SERVER['HTTP_HOST'].'/notify.php',

        'trade_type'    => 'NATIVE',

        'product_id'    => $goods_id

    );

    $unifiedorder['sign'] = self::makeSign($unifiedorder);

    //return $unifiedorder;

    //请求数据,统一下单

    $xmldata = self::array2xml($unifiedorder);

    $url = 'https://api.mch.weixin.qq.com/pay/unifiedorder';

    $res = self::curl_post_ssl($url, $xmldata);

    if(!$res){

        return array('status'=>0, 'msg'=>"Can't connect the server" );

    }

    // 这句file_put_contents是用来查看服务器返回的结果 测试完可以删除了

    file_put_contents('./log.txt',$res,FILE_APPEND);

    $content = self::xml2array($res);

    if(strval($content['result_code']) == 'FAIL'){

        return array('status'=>0, 'msg'=>strval($content['err_code']).':'.strval($content['err_code_des']));

    }

    if(strval($content['return_code']) == 'FAIL'){

        return array('status'=>0, 'msg'=>strval($content['return_msg']));

    }

    return $content;

}

/**

 * 微信退款(POST)

 * @param string(28) $transaction_id    在微信支付的时候,微信服务器生成的订单流水号,在支付通知中有返回

 * @param string $out_refund_no         商品简单描述

 * @param string $total_fee             微信支付的时候支付的总金额(单位:分)

 * @param string $refund_fee            此次要退款金额(单位:分)

 * @return string                       xml格式的数据

 */

public function refund($transaction_id,$out_refund_no,$total_fee,$refund_fee){

    $config = $this->config;

    //退款参数

    $refundorder = array(

        'appid'         => $config['appid'],

        'mch_id'        => $config['mch_id'],

        'nonce_str'     => self::getNonceStr(),

        'transaction_id'=> $transaction_id,

        'out_refund_no' => $out_refund_no,

        'total_fee'     => $total_fee * 100,

        'refund_fee'    => $refund_fee * 100

    );

    $refundorder['sign'] = self::makeSign($refundorder);

    //请求数据,进行退款

    $xmldata = self::array2xml($refundorder);

    $url = 'https://api.mch.weixin.qq.com/secapi/pay/refund';

    $res = self::curl_post_ssl($url, $xmldata);

    if(!$res){

        return array('status'=>0, 'msg'=>"Can't connect the server" );

    }

    // 这句file_put_contents是用来查看服务器返回的结果 测试完可以删除了

    //file_put_contents('./log3.txt',$res,FILE_APPEND);

    $content = self::xml2array($res);

    if(strval($content['result_code']) == 'FAIL'){

        return array('status'=>0, 'msg'=>strval($content['err_code']).':'.strval($content['err_code_des']));

    }

    if(strval($content['return_code']) == 'FAIL'){

        return array('status'=>0, 'msg'=>strval($content['return_msg']));

    }

    return $content;

}

require_once "webwxpay.class.php";

$config = array(

    'appid'         => 'wx123456789876',

    'mch_id'        => '123456789',

    'pay_apikey'    => '123456789876123456789876123456789876'

);

$wxpay = new WxPay($config);

$result = $wxpay->paytest();

//print_r($result);

scerweima($result['code_url']);     //生成的支付二维码,用户可以扫码付款