PHP实现小程序微信支付V2获取prepay_id

PS:本文旨在简单获取prepay_id,只是简单的介绍一下流程,并非完整的订单支付流程

小程序端JS代码:

  getxml(){
   
    var test = this
   wx.getStorage({
       //从缓存中获取用户的openid
      key:'openid',
      success(res){
   
        console.log(res)
        test.setData({
   
          'openid':res.data
        })
        console.log(test.data.openid)
      }
    })
    wx.request({
   
      url: 'http://', //你的URl地址
      method:'POST',
      header:{
   
        'content-type':'application/x-www-form-urlencoded'
      },
      data:{
   
        'openid':test.data.openid,   //用户的opend
        'description':'0.38mm.pen',   //商品描述,此处为简单写了个例子,根据需要进行更改
        'total':1    //商品总金额,单位为分,根据需求可以进行乘100
      },
      success(res){
   
        console.log(res)
      }
    })
  }

PS:这些JS代码通过点击按钮进行触发的,再次重申,本篇文章仅仅只是介绍获取prepay_id的流程,以及本人在写代码过程中遇到的一些问题
PHP代码:

API_connect.php

require_once dirname(__DIR__) .'/getCurl/curlDock.php';

class v2Connect
{
   
    /**
     * @param $URL :访问的API接口地址
     * @param $data :通过POST传递的数据,xml格式
     * @return bool|string :返回数据
     */
    public function connect($URL,$data)
    {
   
        $this->action = curl_init();
        curl_setopt($this->action, CURLOPT_URL, $URL);
        curl_setopt($this->action, CURLOPT_HEADER, 0);
        //curl_setopt($this->action, CURLOPT_HTTPHEADER, 0);
        curl_setopt($this->action, CURLOPT_SSL_VERIFYPEER, 0);
        curl_setopt($this->action, CURLOPT_SSL_VERIFYHOST, 0);
        curl_setopt($this->action, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($this->action,