WordPress如何禁止非管理员、编辑、作者访问后台

function forbid_redirect_wp_admin(){ 
if ( is_admin() && !current_user_can('editor') && ( !defined( 'DOING_AJAX' ) || !DOING_AJAX ) ) {
$current_user = wp_get_current_user();
if($current_user->roles[0] == get_option('default_role')) {
wp_safe_redirect(home_url());
exit();
}
}
}
add_action('init', 'forbid_redirect_wp_admin');

add_action('init', 'qzl_redirect_wp_admin');
function qzl_redirect_wp_admin()
{
    if (is_admin() && is_user_logged_in() && 
    !current_user_can('manage_options') && 
    !current_user_can('publish_pages') && 
    !current_user_can('publish_posts') && 
    (!defined('DOING_AJAX') || !DOING_AJAX)) {
        wp_safe_redirect(home_url());
        exit;
    }
}

wp_safe_redirect(home_url())

wp_safe_redirect('http://www.guimei8.com');

&& !current_user_can('publish_pages') && !current_user_can('publish_posts')