protected function valueToPhone($mask, $value)
    {
        if (substr($value, 0, 1) == "*") { // if phone starts with "*", it's an international number, don't convert it
            return $value;
        }
        if (trim($value) == "") {
            return $value;
        }
        $maskLen = strlen($mask);
        $ph_len = strlen($value);
        $ph_fmt = $mask;
        $j = 0;
        for ($i = 0; $i < $maskLen; $i ++)
        {
            if ($mask[$i] == "#")
            {
                $ph_fmt[$i] = $value[$j];
                $j ++;
                if ($j == $ph_len) {
                    break;
                }
            }
        }
        return substr($ph_fmt, 0, $i + 1);
    }