public function getValue()
    {
        $values = array();
        foreach (array_keys($this->pages) as $id) {
            $pageValues = $this->getSessionContainer()->getValues($id);
            // skip elements representing actions
            foreach ($pageValues as $key => $value) {
                if (0 !== strpos($key, '_qf')) {
                    if (isset($values[$key]) && is_array($value)) {
                        $values[$key] = self::arrayMerge($values[$key], $value);
                    } else {
                        $values[$key] = $value;
                    }
                }
            }
        }
        return $values;
    }