xyzshop/mobile/api/wxLogin/callback.php

<?php
/**
 * Created by PhpStorm.
 * User: james
 * Date: 2017/4/25
 * Time: 下午3:43
 */

include 'config.php';
//判断state是否正确
if(empty($_GET['state'])) {
    exit('参数错误,请重新登录');
}

if($_GET['state'] != $_SESSION['state']) {
    exit('<script>alert("参数错误!"); 
    location.href="../login.php";</script>');
}

//检查用户是否同意授权
if(empty($_GET['code'])) {
    exit('<script>alert("您没有同意授权!"); 
    location.href="../login.php";</script>');
}

/*
 * 通过code换取网页授权access_token
 * https://api.weixin.qq.com/sns/oauth2/access_token?appid=APPID&secret=SECRET&code=CODE&grant_type=authorization_code
 */
$url = 'https://api.weixin.qq.com/sns/oauth2/access_token?appid='.appID.
    '&secret='.appsecret.
    '&code='.$_GET['code'].
    '&grant_type=authorization_code';
//通过curl获取access_token
$res  = myCurl($url);
/*
 * 正确返回
 * { "access_token":"ACCESS_TOKEN","expires_in":7200, "refresh_token":"REFRESH_TOKEN","openid":"OPENID","scope":"SCOPE" }
 * 错误返回
 * {"errcode":40029,"errmsg":"invalid code"}
 */

//将json信息转换为数组
$info = json_decode($res, true);
//判断是否成功
if(empty($info['access_token'])){
    exit('参数错误,请重新登录...');
}

/* 获取用户信息
 * 请求地址：
 * https://api.weixin.qq.com/sns/userinfo?access_token=ACCESS_TOKEN&openid=OPENID&lang=zh_CN
 * 正确时返回的JSON数据包如下：
 * openid 用户的唯一标识
 * nickname 用户昵称
 * 其他相信查看手册
 * 错误时微信会返回JSON数据包如下（示例为openid无效）:
 * {"errcode":40003,"errmsg":" invalid openid "}
*/
$url = 'https://api.weixin.qq.com/sns/userinfo?access_token='.$info['access_token'].'&openid='.$info['openid'].'&lang=zh_CN';
$res  = myCurl($url);
//将json信息转换为数组
$user = json_decode($res, true);
if(!empty($user['errcode'])) {
    exit('参数错误,请重新登录...');
}

//注册session 并返回登录页面
$_SESSION['wxopenid'] = $user['openid'];
$_SESSION['uface']    = $user['headimgurl'];
$_SESSION['uname']    = $user['nickname'];

header('location:');

function myCurl($url, $type = 'GET', $data = null){
    $curl = curl_init();
    curl_setopt($curl, CURLOPT_URL            , $url);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER , true);
    if($type != 'GET'){
        curl_setopt($curl, CURLOPT_POST, 1);
        curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
    }
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER , false);
    curl_setopt($curl, CURLOPT_SSL_VERIFYHOST , false);
    curl_setopt($curl, CURLOPT_ENCODING       , 'gzip,deflate');
    $res  = curl_exec($curl);
    curl_close($curl);
    return $res;
}