微信支付 参考

https://www.cnblogs.com/haoxiaozhang/p/11594523.html 

https://blog.csdn.net/qq_38194393/article/details/88654089

https://www.imooc.com/article/details/id/290941

https://pay.weixin.qq.com/wiki/doc/api/index.html

https://pay.weixin.qq.com/wiki/doc/api/wxa/wxa_api.php?chapter=7_10&index=1