mingde-bd/application/index/common.php

<?php
/**
 * Created by PhpStorm.
 * User: my
 * Date: 2021/7/6
 * Time: 9:15
 */
use think\facade\View;
/**
 * 检测用户是否登录
 * @return integer 0-未登录，大于0-当前登录用户ID
 */
function is_login(){
    $user = session('user_auth');
    if (empty($user)) {
        return 0;
    } else {
        return session('user_auth_sign') == data_auth_sign($user) ? $user['id'] : 0;
    }
}