'; if (!isset($_SESSION['admin'])) { if ($_SERVER['REQUEST_METHOD'] === 'POST' && isset($_POST['username']) && isset($_POST['password'])) { $username = $_POST['username']; $password = $_POST['password']; if ($username === ADMIN_USERNAME && $password === ADMIN_PASSWORD) { $_SESSION['admin'] = [ 'id' => 1, // 配置文件中未定义管理员ID，使用默认值1 'username' => $username ]; header('Location: index.php'); exit(); } else { $error = '用户名或密码错误'; } } // 显示登录表单 echo ''; echo ''; echo ''; echo ' '; echo ' '; echo ' '; echo ' '; echo ' '; echo ' '; echo ' '; echo ' '; echo ' '; echo ''; echo ''; echo ' '; echo ' '; echo ' '; echo ''; echo ''; exit; }