微信OAuth2.0网页授权

这是一个实用且通用的功能，说通俗点就是用微信帐号登录第三方网站，经用户确认后，允许网站获取用户基本资料。

技术资料参见微信官方文档：https://mp.weixin.qq.com/wiki?t=resource/res_main&id=mp1421140842&token=&lang=zh_CN

1、实现这一功能需要先设置授权回调页面域名，如下图：

2、主要代码（只获取用户信息，登录网站部分略）

<?php
if(isset($_GET[‘code‘])){
    $code = $_GET[‘code‘];
    $userInfo = getUserInfo($code);
    echo $userInfo;
}
else{
    echo "Error!";
}

function getUserInfo($code){
    $appid = "wx04d2578db7e1b736";
    $appsecret = "43b9557d223737d01ababb39a4b4b14d";
    $accessToken = "";

    //根据code获取token
    $tokenURL = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=$appid&secret=$appsecret&code=$code&grant_type=authorization_code";
    $tokenJson = https_request($tokenURL);
    $tokenArray = json_decode($tokenJson,true);
    $accssToken = $tokenArray[‘access_token‘];
    $openid = $tokenArray[‘openid‘];

    //拉取用户信息
    $userInfoURL = "https://api.weixin.qq.com/sns/userinfo?access_token=$accssToken&openid=$openid";
    $userInfoJson = https_request($userInfoURL);
    $userInfoArray = json_decode($userInfoJson,true);

    return $userInfoJson;
}

function https_request($url){

    //return $url;
    $curl = curl_init();
    curl_setopt($curl,CURLOPT_URL,$url);
    curl_setopt($curl,CURLOPT_SSL_VERIFYPEER,false);
    curl_setopt($curl,CURLOPT_SSL_VERIFYHOST,false);
    curl_setopt($curl,CURLOPT_RETURNTRANSFER,1);
    $data = curl_exec($curl);
    if(curl_errno($curl)){
        return ‘ERROR‘.curl_error($curl);
    }
    curl_close($curl);
    return $data;
}
?>

3，最后按以下格式访问，获得用户信息

https://open.weixin.qq.com/connect/oauth2/authorize?appid=wx04d2578db7e1b736&redirect_uri=http://essays.duapp.com/getUserInfo.php&response_type=code&scope=snsapi_userinfo&state=STATE#wechat_redirect

返回信息大致如下（未经处理）

{
    "openid": "owThxwlQQV8WQynaTZmMI6yi29-s",
    "nickname": "自由行走",
    "sex": 1,
    "language": "zh_CN",
    "city": "Kunming",
    "province": "Yunnan",
    "country": "CN",
    "headimgurl": "http://wx.qlogo.cn/mmopen/eGrUpN8dpomatpwS0VrRIh6n9deJACV9S9F8vqxjmxicd0Gt5QLl0BNC4zeKSoS24umarmibP7rzf1obOJibVvG9d8icK7cjibTiaE/0",
    "privilege": [ ]
}