Graph::GetLinkURL PHP Method

    protected function GetLinkURL($key, $row = 0)
    {
        if (!is_array($this->links[$row]) || !isset($this->links[$row][$key])) {
            return NULL;
        }
        $link = $this->links[$row][$key];
        if (strpos($link, '//') === FALSE) {
            // check for absolute links
            $link = $this->link_base . $link;
        }
        return $link;
    }