https://dev.weixin.qq.com/docs/framework/dev/jsapi/miniapp/launchMiniProgram.html

需按照指引在微信开放平台创建移动应用账号

console.log("WECHAT_APP_WXA");
            console.log(expend);
            var userName = expend.pay_info.gh_appid;
            var ll_token = expend.pay_info.token;
            let path = "pages/pay/index?token=" + ll_token;
            console.log(path);
            wx.miniapp.launchMiniProgram({
              userName:userName,
              path:path,
              miniprogramType:0,
              success(res) {
                console.log(res);
                // 打开成功
              },
              fail(res) {
                console.log(res);
                // 失败成功
              }
            })