Source of file SiteMapController.php

<?php

namespace WebOfTalent\PageSiteMap;

use SilverStripe\ErrorPage\ErrorPage;

use SilverStripe\Core\Convert;

use SilverStripe\ORM\DataObject;

class SiteMapController extends \PageController

{

    /**

    * This function will return a unordered list of all pages on the site.

    * Watch for the switch between $page and $child in the second line of the

    * foreach().

    *

    * Note that this will only skip ErrorPage's at the top/root level of the site.

    * If you have an ErrorPage class somewhere else in the hierarchy, it will be

    * displayed.

    */

    public function SiteMap()

    {

        // Pages at the root level only

        $rootLevel = \Page::get()->filter('ParentID', 0);

        $output = '';

        $output = $this->makeList($rootLevel);

        return $output;

    }

    private function makeList($pages)

    {

        $output = '';

        if (count($pages)) {

            $output = '

			<ul>';

            foreach ($pages as $page) {

                if (!($page instanceof ErrorPage) && $page->ShowInMenus && $page->Title != $this->Title) {

                    $output .= '

					<li><a href="'.$page->URLSegment.'" title="Go to the '.Convert::raw2xml($page->Title).' page">'.Convert::raw2xml($page->MenuTitle).'</a>';

                    $whereStatement = 'ParentID = '.$page->ID;

                    $childPages = DataObject::get('Page', $whereStatement);

                    $output .= $this->makeList($childPages);

                    $output .= '</li>';

                }

            }

            $output .= '

			</ul>';

        }

        return $output;

    }

}