电子商务制造商列表中的CSS活动类

我正试图为OSCommerce的Bootstrap主题添加一个针对制造商的活动类。我对PHP一窍不通，无法完成它。有谁能帮我吗？

代码

  $manufacturers_list = '<ul class="nav nav-pills nav-stacked">';
  while ($manufacturers = tep_db_fetch_array($manufacturers_query)) 
  {
    $manufacturers_name = ((strlen($manufacturers['manufacturers_name']) > MAX_DISPLAY_MANUFACTURER_NAME_LEN) ? substr($manufacturers['manufacturers_name'], 0, MAX_DISPLAY_MANUFACTURER_NAME_LEN) . '..' : $manufacturers['manufacturers_name']);
    if (isset($HTTP_GET_VARS['manufacturers_id']) && ($HTTP_GET_VARS['manufacturers_id'] == $manufacturers['manufacturers_id'])) 
        $manufacturers_name = '<strong>' . $manufacturers_name .'</strong>';
        $manufacturers_list .= '<li><a href="' . tep_href_link(FILENAME_DEFAULT, 'manufacturers_id=' . $manufacturers['manufacturers_id']) . '">' . $manufacturers_name . '</a></li>';  
  }
  $manufacturers_list .= '</ul>';

我想我可以像这里一样编码

$manufacturers_list .= '<li><a' if (isset($manufacturor_name)) {echo "class="'active'} ' href="' . tep_href_link(FILENAME_DEFAULT, 'manufacturers_id=' . $manufacturers['manufacturers_id']) . '">' . $manufacturers_name . '</a></li>';

谢谢你的建议。