public function capitalize($string)
    {
        if (!extension_loaded('mbstring')) {
            return ucfirst($string);
        }

        $encoding = Yii::app()->charset;
        $firstChar = mb_strtoupper(mb_substr($string, 0, 1, $encoding), $encoding);
        return $firstChar . mb_substr($string, 1, mb_strlen($string, $encoding) - 1, $encoding);
    }