内网 IPAddress ipAddr = Dns.Resolve(Dns.GetHostName()).AddressList[0];//获得当前IP地址            string ip = ipAddr.ToString();

外网

//获取本机的公网IP        public static string GetPublicNetworkIP()        {            string tempip = "";            WebRequest request = WebRequest.Create("http://ip.qq.com");            request.Timeout = 10000;            WebResponse response = request.GetResponse();            Stream resStream = response.GetResponseStream();            StreamReader sr = new StreamReader(resStream, System.Text.Encoding.Default);            string htmlinfo = sr.ReadToEnd();            //匹配IP的正则表达式            Regex r = new Regex("((25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]\\d|\\d)\\.){3}(25[0-5]|2[0-4]\\d|1\\d\\d|[1-9]\\d|[1-9])", RegexOptions.None);            Match mc = r.Match(htmlinfo);            //获取匹配到的IP            tempip = mc.Groups[0].Value;            resStream.Close();            sr.Close();            return tempip;        }

强制退出程序 

System.Environment.Exit(System.Environment.ExitCode);