/**
  * export bookmarks
  */
 function export($deliver = true)
 {
     $bm_ids = $_GET['bm_id'] ? array($_GET['bm_id']) : $_POST['bm_id'];
     if (!$bm_ids) {
         $this->ilias->raiseError($this->lng->txt("no_checkbox"), $this->ilias->error_obj->MESSAGE);
     }
     $export_ids = array();
     foreach ($bm_ids as $id) {
         if ($this->tree->isInTree($id)) {
             //list($type, $obj_id) = explode(":", $id);
             //$export_ids[]=$obj_id;
             $export_ids[] = $id;
         }
     }
     require_once "./Services/Bookmarks/classes/class.ilBookmarkImportExport.php";
     $html_content = ilBookmarkImportExport::_exportBookmark($export_ids, true, $this->lng->txt("bookmarks_of") . " " . $this->ilias->account->getFullname());
     if ($deliver) {
         ilUtil::deliverData($html_content, 'bookmarks.html', "application/save", $charset = "");
     } else {
         return $html_content;
     }
 }