合单支付基本在加盟店或是分公司或是营销系统里面常见。他的出现，打破了传统提现支付或是转账支付。他的业务原理其实很简单，就是需要优先申请非普通商户，其次是每个入驻的商户都需要申请普通商户。在这之前一定要申请好对应的场景服务，比如公众号支付就需要优先申请公众号，小程序支付就需要优先申请小程序，APP支付就需要提供APP应用ID(在开放平台申请)，PC网站支付就需要优先提供网站授权函，如果是企业微信支付，就需要提供企业微信。

一、支付产品流程图

二、微信支付工具集代码开发

<?php
/*** 微信合单支付工具* User: 龙哥·三年风水* Date: 2024/9/27* Time: 14:13*/
namespace app\service;
use app\BaseError;
class WechatCooperatePayment
{protected $combineMchid = null;// 合单商户号protected $merchantSerialNumber = null;// 商户API证书序列号protected $combineAppid = null;// 合单商户Appidprotected $merchantPrivateKey = null;// 商户私钥/*** 初始化参数* WechatPayment constructor.*/public function __construct(){$this->combineMchid = config('pay.wechat.combine_appid');$this->combineAppid = config('pay.wechat.app_id');$this->merchantSerialNumber = config('pay.wechat.merchant_serial_number');$file = file_get_contents('./wechatpay/apiclient_key.pem');$this->merchantPrivateKey = openssl_get_privatekey($file);// 读取商户秘钥}/*** 合单支付* User: 龙哥·三年风水* Date: 2024/9/27* Time: 14:21* @ param $url* @ param $data* @ return mixed*/public function combinePay($url,$data){$data['combine_mchid'] = $this->combineMchid;$data['combine_appid'] = $this->combineAppid;$authorization = $this->getSign($url,$data);$res = http_post($url, $authorization, $data);$arr = json_decode($res, true);if(isset($arr['code'])) {$error['code'] = $arr['code'];$error['message'] = $arr['message'];$error['timestamp'] = time();$error['ip'] = get_client_ip();file_put_contents('wechat_payment.txt', json_encode($error) . PHP_EOL, FILE_APPEND);throw new BaseError($arr['message'], 50000, 200);}return $arr;}/*** 获取签名* User: 龙哥·三年风水* Date: 2024/9/27* Time: 9:23* @ param $url 地址* @ param $data 数据* @ return string 返回*/private function getSign($url,$data){$timestamp = time();$nonce = alnum(12).date('YmdHis', $timestamp) . rand(1000, 9999);$url_parts = parse_url($url);$canonical_url = ($url_parts['path'] . (!empty($url_parts['query']) ? "?${url_parts['query']}" : ""));$data = json_encode($data);$message = 'POST' . "\n" .$canonical_url . "\n" .$timestamp . "\n" .$nonce . "\n" .$data . "\n";openssl_sign($message, $signature, $this->merchantPrivateKey, "sha256WithRSAEncryption");$sign = base64_encode($signature);$schema = 'WECHATPAY2-SHA256-RSA2048';$token = sprintf('mchid="%s",nonce_str="%s",timestamp="%d",serial_no="%s",signature="%s"',  $this->combineMchid, $nonce, $timestamp, $this->merchantSerialNumber, $sign);return "Authorization: " . $schema . " " . $token;}/*** 销毁参数*/public function __destruct(){$this->combineMchid = null;$this->combineAppid = null;$this->merchantSerialNumber = null;$this->merchantPrivateKey = null;}
}

三、测试JSAPI支付订单调用

public function index(){//定义参数$data['combine_out_trade_no'] = create_order();$data['sub_orders'] =   [['mchid'     =>  '1230000109','attach'    =>  '深圳分店','amount'    =>  ['total_amount'  =>  10,'currency'      =>  'CNY'],'out_trade_no'  =>  create_order(),'description'   =>  '运费钱']];$data['combine_payer_info'] =   ['combine_payer_info'    =>  'oUpF8uMuAJO_M2pxb1Q9zNjWeS6o'];$data['notify_url'] =   'http://www.baidu.com';$wechatCooperatePayment = new WechatCooperatePayment();$res = $wechatCooperatePayment->combinePay('https://api.mch.weixin.qq.com/v3/combine-transactions/jsapi',$data);var_dump($res);
}