WeChat cloud development - get the user's openid and set it as a global variable

Create a cloud function

As shown in the figure, create a cloud function and upload it

// 云函数入口文件
const cloud = require('wx-server-sdk')
cloud.init({
    
     env: cloud.DYNAMIC_CURRENT_ENV }) // 使用当前云环境
// 云函数入口函数
exports.main = async (event, context) => {
    
    
  const wxContext = cloud.getWXContext()
  return {
    
    
    event,
    openid: wxContext.OPENID,
    appid: wxContext.APPID,
    unionid: wxContext.UNIONID,
  }
}

Initialize cloud development

Initialize the cloud function in app.js in the root directory

App({
    
    
  onLaunch:function(){
    
    
    //云开发环境测试
    wx.cloud.init({
    
    
      env:"qfb-7ghqo63b396f0b1f"
    })
    wx.cloud.callFunction({
    
    
      name: 'get_openId',
      success: res => {
    
    
        //获取用户openid
        this.globalData.user_openid = res.result.openid
        console.log(this.globalData.user_openid)
      }
    })
   },

As shown in the figure, the user's openid is printed in the debugger, which is consistent with the openid in the cloud database.

global call

In the previous step, the openid has been stored in globalData, so the openid can be used in any file.

console.log("这是全局变量Openid"+app.globalData.user_openid,res)

As shown in the figure, the call is successful