C#取得内网IP、外网IP、客户端IP方法

 

前言

　　在 Windows Form Application 里对于取得 IP Address 有内网、外网两种 IP Address ，如果只需要取得内网 IP Address ，可以透过使用 IPHostEntry 类别取得，而外网的话就必须要发送一个 Request 到一个可以取得 IP Address 的网站后再分析 Response 的内容，这个网站可以自己做或者使用现成的，如 http://www.whatismyip.com.tw/ 。

　　另外，在使用 Socket 通讯的情况下，也有可能有需要知道前来连结的客户端的 IP Address 是什么，这时就可以使用 Socket.RemoteEndPoint 属性来取得远程 IP 地址和通讯端口编号，以下就列出范例代码看看该如何使用。

范例程序代码

/// <summary>

        /// 取得外网 IP Address

        /// </summary>

        /// <returns></returns>

        private string GetExtranetIPAddress()

        {

            HttpWebRequest request = HttpWebRequest.Create("http://www.whatismyip.com.tw") as HttpWebRequest;

            request.Method = "GET";

            request.ContentType = "application/x-www-form-urlencoded";

            request.UserAgent = "Mozilla/5.0";

            string ip = string.Empty;

            WebResponse response = request.GetResponse();

            using (StreamReader reader = new StreamReader(response.GetResponseStream()))

            {

                string result = reader.ReadToEnd();

                string pattern = @"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}";

                ip = Regex.Match(result, pattern).ToString();

            }

            return ip; // result: 210.125.21.xxx

        }

取得外网 IP Address

/// <summary>

        /// 取得本机 IP Address

        /// </summary>

        /// <returns></returns>

        private List<string> GetHostIPAddress()

        {

            List<string> lstIPAddress = new List<string>();

            IPHostEntry IpEntry = Dns.GetHostEntry(Dns.GetHostName());

            foreach (IPAddress ipa in IpEntry.AddressList)

            {

                if (ipa.AddressFamily == AddressFamily.InterNetwork)

                    lstIPAddress.Add(ipa.ToString());

            }

            return lstIPAddress; // result: 192.168.1.17 ......

        }

取得本机 IP Address

 

private static string GetIP()

{

    string tempip = "";

    try

    {

        WebRequest wr = WebRequest.Create("http://www.ip138.com/ips138.asp");

        Stream s = wr.GetResponse().GetResponseStream();

        StreamReader sr = new StreamReader(s, Encoding.Default);

        string all = sr.ReadToEnd(); //读取网站的数据



        int start = all.IndexOf("您的IP地址是：[") + 9;

        int end = all.IndexOf("]", start);

        tempip = all.Substring(start, end - start);

        sr.Close();

        s.Close();

    }

    catch

    {

    }

    return tempip;

}

取得外网ip

 

 

 

/// <summary>

/// 执行服务器监听

/// </summary>

public static void RunServer() 

{



    // 建立X509凭证

    ServerCertificate = new X509Certificate(Certificate, "ssl");

    // 监听任何IP Address来的讯息

    listener = new TcpListener(System.Net.IPAddress.Any, 17170);

    // 开启监听

    listener.Start();



    while (IsRun)

    {

        TcpClient client = listener.AcceptTcpClient();



        ProcessClient(client);

    }

}



/// <summary>

/// 接收客户端讯息处理并回复

/// </summary>

/// <param name="pClient"></param>

private static void ProcessClient(TcpClient pClient)

{

    SslStream sslStream = new SslStream(pClient.GetStream(), true);



    // 取得连接者 IP 与 Port

    IPEndPoint point = pClient.Client.RemoteEndPoint as IPEndPoint;

    string ip = point.Address.ToString(); // result: 127.0.0.1

    string port = point.Port.ToString(); // result: 55236



    // do something...

}

Socket 取得远程 IP Address 与 Port

 

string tempIP =string.Empty;if (System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList.Length >1)     tempIP = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList[1].ToString();

如果是ADSL上网，获取公网ip