微信授权登录类

<?php
/**
 * 微信授权登录类
 * User: chenzhijian
 * Date: 2016/3/24
 * Time: 14:26
 */
namespace WxLogin;

class Wxlogin{

    //AppId（应用ID）
    private $appid = "*******";
    //AppSecret（应用密钥）
    private $appSecret = "*********";
    //code （同意授权后的code）
    private $code = "";
    //access_token（网页授权后获取）
    private $accessToken = "";
    //返回类型
    private $responseType='code';
    //scope 返回用户类型字段  nsapi_base | snsapi_userinfo
    private $scope = "snsapi_userinfo";
    //请求微信url
    private $url = "https://open.weixin.qq.com/connect/oauth2/authorize";
    //请求微信api_url
    private $apiUrl = "https://api.weixin.qq.com/sns";
    //回调地址
    private $redireUri = "http://xxx.com/callback";

    public function __construct(){

    }
    /*
     * 获取code
     * explame https://open.weixin.qq.com/connect/oauth2/authorize?appid=****&redirect_uri=http://www.xxx.com&response_type=code&scope=snsapi_userinfo&state=233232#wechat_redirect
     * return http://m.mkf.com/?code=0216ec79275a460d201e0cee2631f70X&state=KlhsiE%23wechat_redirect
     */
    public function getCode(){
        $param = array(
          'appid'=>  $this->appid,       //AppId（应用ID）
          'redirect_uri'=>  $this->redireUri,  //授权后重定向的回调链接地址，请使用urlencode对链接进行处理
          'response_type'=> $this->responseType,  //返回类型
          'scope'=>   $this->scope,                               //scope 返回用户类型字段
          'state' =>  $this->randString(6).'#wechat_redirect'    //重定向后会带上state参数
        );
        $param =http_build_query($param);
        $url = $this->url.'?'.$param;
        redirect($url);
    }
    /*
     * explame https://api.weixin.qq.com/sns/oauth2/access_token?appid=xxxxx&secret=xxxx&code=0216ec79275a460d201e0cee2631f70X&grant_type=authorization_code
     * 获取access_token
     * @return json access_token  expires_in refresh_token openid scope
     */
    public function getAccessToken($code){
        $code = $code ? $code : trim($_GET['code']);        //code
        $param = array(
            'appid'=>  $this->appid,       //AppId（应用ID）
            'secret'=>  $this->appSecret,  //AppSecret（应用密钥）
            'code'=> $code,     //code
            'grant_type'=>  'authorization_code',    //authorization_code
        );
        //请求api地址
        $url = $this->apiUrl.'/oauth2/access_token';
        $result = $this->getCurl($url,$param);
        return $result;
    }

    /*
     * example https://api.weixin.qq.com/sns/userinfo?access_token=xxx-xx&openid=xxx
     * 获取微信用户信息
     * @return array
     */
    public function getUserInfo($access_token,$openid){
        $param = array(
            'access_token'=>  $access_token,             //网页授权凭证
            'openid'=> $openid          //用户的唯一标识
        );
        //请求api地址
        $url = $this->apiUrl.'/userinfo';
        $result = $this->getCurl($url,$param);
        return $result;

    }
    /**
     * explame https://api.weixin.qq.com/sns/oauth2/refresh_token?appid=xxx&grant_type=refresh_token&refresh_token=REFRESH_TOKEN
     * 获取access_token
     * @return json access_token  expires_in refresh_token openid scope
     */
    public function refreshAccessToken($openid,$refresh_token){
        $refresh_token = trim($refresh_token);
        $param = array(
            'appid'=>$openid,
            'grant_type'=>'refresh_token',
            'refresh_token'=>$refresh_token
        );
        //请求api地址
        $url = $this->apiUrl.'/oauth2/refresh_token';
        $result = $this->getCurl($url,$param);
        return $result;
    }
    //随机数
    public function randString($len=6){
        $chars = array(
            "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k",
            "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v",
            "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G",
            "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R",
            "S", "T", "U", "V", "W", "X", "Y", "Z"
        );
        $charsLen = count($chars) - 1;
        // 将数组打乱
        shuffle($chars);
        $output = "";
        for ($i = 0; $i < $len; $i++) {
            $output .= $chars[mt_rand(0, $charsLen)];
        }
        return $output;
    }


    //curl调用
    public function getCurl($domain='',$param){
        $param =http_build_query($param);
        $url = $domain.'?'.$param;
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_HEADER, 0);
        $result = curl_exec($ch);
        curl_close($ch);
        $result = json_decode($result,true);
        return $result;
    }




}