PHP微信扫码关注公众号并授权登录【原创】

第一步：获取关注二维码ticket,并且传参二维码qrcode表主键id

$sql = "INSERT INTO `qrcode` (`addtime`) VALUES ('" . time() . "')";

mysql_query($sql);
$scene_id = mysql_insert_id();

$url = 'https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=' . $appid . '&secret=' . $appsecret;
$access_token_array = json_decode(curlGet($url), true);
$access_token = $access_token_array['access_token'];
//echo $access_token;exit;http://www.sucaihuo.com/project/wxvalid/index.php 
$qrcode_url = 'https://api.weixin.qq.com/cgi-bin/qrcode/create?access_token=' . $access_token;

$post_data = array();
$post_data['expire_seconds'] = 3600 * 24; //有效时间
$post_data['action_name'] = 'QR_SCENE';
$post_data['action_info']['scene']['scene_id'] = $scene_id; //传参用户uid，微信端可获取
$json = curlPost($qrcode_url, json_encode($post_data));
if (!$json['errcode']) {

    $ticket = $json['ticket'];
    $ticket_img = 'https://mp.weixin.qq.com/cgi-bin/showqrcode?ticket=' . urlencode($ticket);
} else {
    echo '发生错误：错误代码 ' . $json['errcode'] . '，微信返回错误信息：' . $json['errmsg'];
    exit;
}

第二步：微信服务端接受数据，并且用户登录信息

$postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
$scene_id = str_replace("qrscene_", "", $postObj->EventKey);

$openid = $postObj->FromUserName; //openid
$ToUserName = $postObj->ToUserName;  //转换角色
$Event = strtolower($postObj->Event);
if ($Event == 'subscribe') {//首次关注
    $is_first = 0;
} elseif ($Event == 'scan') {//已关注
    $is_first = 1;
}
$access_token = $this->getAccessToken();

$userinfo = $this->getUserinfo($openid, $access_token);
$sql = "UPDATE `qrcode` SET `openid` = '" . $openid . "',logintime='" . time() . "',is_first=" . $is_first . ",nickname='" . $userinfo['nickname'] . "'"
        . ",avatar='" . $userinfo['avatar'] . "',sex='" . $userinfo['sex'] . "',province='" . $userinfo['province'] . "',city='" . $userinfo['city'] . "',country='" . $userinfo['country'] . "' WHERE `id` =" . $scene_id . "";

mysql_query($sql);

第三步：每隔2秒检测是否关注微信公众号

<script>
    check_login();
    function check_login() {
        $.post("check_login.php", {scene_id: <?php echo $scene_id; ?>}, function(data) {
            var attention = '首次关注';
            if (data.is_first == 1) {
                attention = '已关注过';
            }
            if (data.openid != null) {
                alert("扫码成功，openid为" + data.openid + "nickname:" + data.nickname);
                location.reload();

            } else {
                setTimeout("check_login()", 2000);
            }
        }, "json");
    }
</script>

通过微信openid和access_token获取微信用户信息，并存入表当中的信息如下：

<tr>
    <th>openid</th>
    <th>昵称</th>
    <th>性别</th>
    <th>国家</th>
    <th>省份</th>
    <th>城市</th>
    <th>头像</th>
    <th>是否关注过</th>
    <th>登录时间</th>
</tr>

若是没有获取到数据，记得开启curl，检查防火墙、启用截图如下

微信服务器IP白名单设置

PHP扫码关注公众号更新日志

2021-1-22 
1、修复因服务器配置导致的BUG
2、修复第一次关注无法获取用户信息（由于微信接口变化）
3、增加调试报错信息，比如因curl未开启，或者访问腾讯https出现SSL certificate：unable to get local issuer certificate
4、取消腾讯远程curl对https验证