[C#] IP주소 알아내기

        private string getIP()
        {
            Regex regex = new Regex(@"^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$");
            foreach (System.Net.IPAddress ip in System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList)
            {
                if (regex.IsMatch(ip.ToString()))
                {
                    return ip.ToString();
                }
            }
            return null;
        }