这是如何做到的：

add_action(\'admin_menu\' , \'add_to_cpt_menu\'); 

function add_to_cpt_menu() {
    add_submenu_page(\'edit.php?post_type=name_of_post_type\', \'Custom Post Type Admin\', \'Custom Settings\', \'edit_posts\', basename(__FILE__), \'cpt_menu_function\');
}   

添加菜单和子菜单，如：

add_action(\'admin_menu\', \'custom_plugin_menu\');
function custom_plugin_menu() {
    $page_title = \'Parent Menu Title\';
    $menu_title = \'Parent Menu Title\';
    $capability = \'manage_options\';
    $menu_slug = \'parent_menu_slug\';
    $function = \'whatever_for_main_page_function\';
    $icon_url = \'dashicons-admin-generic\';
    $position = 4;
    add_menu_page($page_title, $menu_title, $capability, $menu_slug, $function, $icon_url, $position);

    $parent_slug = \'parent_menu_slug\';
    $page_title = \'Submenu Page Title\';
    $menu_title = \'Submenu Page Title\';
    $capability = \'manage_options\';
    $menu_slug = \'edit-tags.php?taxonomy=your_taxonomy_name&post_type=custom_post_type_name\';
    $function = null;
    $position = null;
    add_submenu_page($parent_slug, $page_title, $menu_title, $capability, $menu_slug, $function, $position);
}

add_filter(\'parent_file\', \'menu_highlight\');    
function menu_highlight($parent_file) {
    global $plugin_page, $submenu_file, $post_type, $taxonomy;
    if (\'custom_post_type_name\' == $post_type) {
        if ($taxonomy == \'your_taxonomy_name\') {
            $plugin_page = \'edit-tags.php?taxonomy= your_taxonomy_name&post_type= custom_post_type_name\'; // the submenu slug 
            $submenu_file = \'edit-tags.php?taxonomy= your_taxonomy_name&post_type= custom_post_type_name\';    // the submenu slug
        }
    } 
    return $parent_file;
}