相关疑难解决方法(0)

我的class.inc文件:

<?php
class logout{
    public function logout(){
        $_SESSION = array();
        if (ini_get("session.use_cookies")) {
            $params = session_get_cookie_params();
            setcookie(session_name(), '', time() - 42000, $params['path'], $params['domain'], $params['secure'], $params["httponly"]);
        }
        session_destroy();
    }   
}

?>

用于注销的代码:

session_start();
require($path."include/class.inc");
if(!empty($_GET['logout'])){
    $object=new logout();
    $object->logout();
    $content='5;url='.$path.'index.php';
}

logout调用该函数时,它会销毁会话,但会显示警告:

Warning: session_destroy(): Trying to destroy uninitialized session in class.inc on line 9

我无法排除故障,如会话没有被任何其他方式破坏之前session_destroy()的class.inc.