微信公众号授权

1.公众号后台配置授权域名比如（www.xiaozhu.com）

 直接获取用户的openid

 前端
created() {
        this.getCode();
    },

    methods: {
        getCode() {
　　　　　　　　//APPID 是公众号的appid 
　　　　　　　　//https://www.xiaozhu.com/index/test/get_openid  授权获取openid

            let local = 'https://www.xiaozhu.com/index/test/get_openid';
            window.location.href =
                "https://open.weixin.qq.com/connect/oauth2/authorize?appid=" +
                AppID +
                "&redirect_uri=" +
                encodeURIComponent(local) +
                "&response_type=code&scope=snsapi_base&state=STATE#wechat_redirect";
        }
    }

后端

public function get_openid(){
    $code = input('param.code');
    $url  = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=".$this->appid."&secret=".$this->secret."&code=".$code. "&grant_type=authorization_code";

    $res  = file_get_contents($url);
    $data = json_decode($res, true);

    var_dump($data);die;

}