C# 외부IP 획득하기

//URL에서 IP획득

string searchIpFromUrl = new System.Net.WebClient().DownloadString(("http://checkip.dyndns.org"));

//자를부분

        string EtcIpInfo = searchIpFromUrl.Substring(searchIpFromUrl.IndexOf("</body>"), searchIpFromUrl.Length - searchIpFromUrl.IndexOf("</body>"));

//전체에서 시작점~ 전체길이-앞뒤자를부분

        string serverIp = searchIpFromUrl.Substring(searchIpFromUrl.IndexOf(":") + 1, searchIpFromUrl.Length - searchIpFromUrl.IndexOf(":") - EtcIpInfo.Length - 1).Trim();