可以使用全局变量$submenu.

列出父post菜单的子菜单的示例：-

function admin_init_callback() {
    global $submenu;
    $sumenu_list = $submenu[\'edit.php\'];
    var_dump($sumenu_list); //array of submenu
}
add_action(\'admin_init\', \'admin_init_callback\', 999);