微信小程序+php 授权登陆，完整代码

<view wx:if="{{isHide}}">
    <view wx:if="{{canIUse}}" >
        <view class='header'>
            <image src='/images/icon/wx_login.png'></image>
        </view>
 
        <view class='content'>
            <view>申请获取以下权限</view>
            <text>获得你的公开信息(昵称，头像等)</text>
        </view>
 
        <button class='bottom' type='primary' open-type="getUserInfo" lang="zh_CN" bindgetuserinfo="bindGetUserInfo">
            授权登录
        </button>
    </view>
    <view wx:else>请升级微信版本</view>
</view>
 
<view wx:else>
    <view>我的首页内容</view>
</view>

.header {
    margin: 90rpx 0 90rpx 50rpx;
    border-bottom: 1px solid #ccc;
    text-align: center;
    width: 650rpx;
    height: 300rpx;
    line-height: 450rpx;
}
 
.header image {
    width: 200rpx;
    height: 200rpx;
}
 
.content {
    margin-left: 50rpx;
    margin-bottom: 90rpx;
}
 
.content text {
    display: block;
    color: #9d9d9d;
    margin-top: 40rpx;
}
 
.bottom {
    border-radius: 80rpx;
    margin: 70rpx 50rpx;
    font-size: 35rpx;
}

// pages/test1/test1.js
var app = getApp();
Page({

  /**
   * 页面的初始数据
   */
  data: {
    //判断小程序的API，回调，参数，组件等是否在当前版本可用。
    canIUse: wx.canIUse('button.open-type.getUserInfo'),
    isHide: false
  },

  /**
   * 生命周期函数--监听页面加载
   */
  onLoad: function (options) {
    var that = this;
    // 查看是否授权
    wx.getSetting({
      success: function (res) {
        if (!res.authSetting['scope.userInfo']) {
          // 还未授权，显示授权按钮
          that.setData({
            isHide: true
          });
        } else {
          // 已授权，隐藏授权按钮，显示正文
          that.setData({
            isHide: false
          });
        }
      }
    })
  },

  //授权登陆按钮
  bindGetUserInfo: function (e) {
    var that = this;
    console.log(e)
    if (e.detail.userInfo) {
      //用户授权登陆，并跳转首页
      // that.getOpenid()
      wx.login({
        success: function (res) {
          // 请求自己后台获取用户openid
          wx.request({
            url: app.domain + 'teacherapi/Wx_Decode/WxDecode',
            method: 'POST',
            header: { 'content-type': 'application/x-www-form-urlencoded' },
            data: {
              encryptedData: e.detail.encryptedData,
              signature: e.detail.signature,
              rawData: e.detail.rawData,
              iv: e.detail.iv,
              code: res.code
            },
            success: function (res_user) {
              if (res_user.data.status == 0) {
                var data = JSON.parse(res_user.data.msg)　　　　//json转对象
                //授权成功返回的数据，根据自己需求操作
                console.log(data)

                //授权成功后，隐藏授权按钮，显示正文
                that.setData({
                  isHide: false
                });
              }
            }, fail: function () {
              that.showModal('获取授权信息失败')
            }
          })
        }
      })
    } else {
      //用户按了拒绝授权按钮，提示引导授权
      that.showModal('请授权后使用小程序')
    }
  },

  //未授权弹窗
  showModal: function (e) {
    wx.showModal({
      title: '提示',
      content: e,
      showCancel: false,
      confirmText: '返回授权',
      success: function (res) {
        if (res.confirm) {
          console.log('用户点击了“返回授权”')
        }
      }
    })
  },

})

<?php
namespace app\teacherapi\controller;
use think\Controller;
/**
* @date: 2018-12
* 微信操作类
*/

class WxDecode extends Controller
{
    public function httpGet($url) {
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_TIMEOUT, 500);
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($curl, CURLOPT_URL, $url);
        $res = curl_exec($curl);
        curl_close($curl);
        return $res;
    }

    /**
     * @author: zxf
     * @date: 2018-12-08
     * @description: 解密微信用户敏感数据
     * @return array
     */
    public function WxDecode()
    {
        // 接收参数
        $data = request() -> param();
        

        // 引入解密文件 在微信小程序开发文档下载
        vendor('wx.WXBizDataCrypt');
        vendor('wx.ErrorCode');

        $appid = config('TESTPPID');
        $appsecret = config('TESTSECREET');
        $grant_type = "authorization_code"; //授权（必填）

        $code = $data['code'];        //有效期5分钟 登录会话

        $encryptedData=$data['encryptedData'];
        $iv = $data['iv'];
        $signature = $data['signature'];
        $rawData = $data['rawData'];

        // 拼接url
        $url = "https://api.weixin.qq.com/sns/jscode2session?"."appid=".$appid."&secret=".$appsecret."&js_code=".$code."&grant_type=".$grant_type;
        $res = json_decode($this->httpGet($url),true);


        $sessionKey = $res['session_key']; //取出json里对应的值
        $signature2 =  sha1(htmlspecialchars_decode($rawData).$sessionKey);
        // 验证签名
        if ($signature2 !== $signature){
            return json("验签失败");
        } 

        // 获取解密后的数据
        $pc = new \WXBizDataCrypt($appid, $sessionKey);
        $errCode = $pc->decryptData($encryptedData, $iv, $data );

        if ($errCode == 0) {
            return return_succ($data);
        } else {
            return return_error($errCode);
        }
    }
        
}