open-wechat JS-SDK https://developers.weixin.qq.com/doc/offiaccount/OA_Web_Apps/JS-SDK.html 微信支付 https://pay.weixin.qq.com/wiki/doc/apiv3/wxpay/pages/index.shtml 小程序 https://mp.weixin.qq.com/cgi-bin/wx 开放平台 https://open.weixin.qq.com/