LdapTools\Query\Operator\ContainsOperatorsTrait::toLdapFilter PHP Method

    public function toLdapFilter($alias = null)
    {
        $innerFilter = $this->getChildrenFilterString($alias);
        if (empty($innerFilter)) {
            return '';
        }
        return self::SEPARATOR_START . self::SYMBOL . $innerFilter . self::SEPARATOR_END;
    }