Udp通信

有了筆記（二）中的積累，udp的感覺就簡單多了。

#region usings

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

using System.Net;

using System.Net.Sockets;

using System.Threading;

#endregion

namespace NetStudy

{

    delegate void AppendItem(object o);

    public partial class MyTalkUdp : Form

    {

        #region Vars

        Thread serverThread;

        EndPoint  remoteIpep;

        Socket serverSock, clicentSock;

        AppendItem AddItem;

        void addItem(object o)

        {

            listBox.Items.Add(o);

        }

        string message;

        #endregion

        #region Constructions

        public MyTalkUdp()

            InitializeComponent();

            AddItem = new AppendItem(addItem);

        #region Events

        private void btSent_Click(object sender, EventArgs e)

            IPAddress[] ipalist = Dns.GetHostAddresses(txtTarget.Text.Trim());

            if (ipalist.GetLength(0) <= 0)

            {

                listBox.Items.Add("Invalid Target!");

                return;

            }

            IPAddress ipa = ipalist[0];

            remoteIpep = new IPEndPoint(ipa, 8989);

            message = txtMessage.Text;

            txtMessage.Clear();

            SentMessage();

            listBox.Items.Add("TO " + remoteIpep.ToString() + ":" + message);

        private void MyTalkUdp_Load(object sender, EventArgs e)

            serverThread = new Thread(new ThreadStart(StartListen));

            serverThread.Start();

        #region Methods

        void StartListen()

            serverSock = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

            serverSock.Bind(new IPEndPoint(IPAddress.Any, 8989));

            byte[] buf=new byte[1024];

            IPEndPoint remotePoint=null;

            int bufLen = 0;

            bool isKeepAlive=true;

            string data;

            while (isKeepAlive)

                try

                {

                    bufLen = serverSock.Available;

                    if (bufLen != 0)

                    {

                        serverSock.ReceiveFrom(buf, SocketFlags.None,ref remoteIpep);

                        data=System.Text.Encoding.Unicode.GetString(buf, 0, bufLen);

                        if (!string.IsNullOrEmpty(data))

                        {

                            listBox.Invoke(AddItem, "FROM " + remoteIpep.ToString() + ":" + data);

                        }

                    }

                }

                catch (SocketException sexc)

                    listBox.Invoke(AddItem, sexc.Message);

        void SentMessage()

            if (string.IsNullOrEmpty(message)) return;

            buf = System.Text.Encoding.Unicode.GetBytes(message);

            clicentSock = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

            try

                clicentSock.SendTo(buf, remoteIpep);

            catch (SocketException sexc)

                listBox.Items.Add(sexc.Message);

    }

}

本文轉自today4king部落格園部落格，原文連結：http://www.cnblogs.com/jinzhao/archive/2008/08/05/1260794.html，如需轉載請自行聯系原作者