c# UDP通信 列子

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net.Sockets;
using System.Net;
using System.Threading;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            IPAddress[] ips = Dns.GetHostAddresses("");
            this.textBox1.Text = ips[0].ToString();
            this.textBox4.Text = ips[0].ToString();

        }

        private void textBox1_TextChanged(object sender, EventArgs e)
        {
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            Control.CheckForIllegalCrossThreadCalls = false;
        }
        Socket mySocket;
        IPEndPoint Remoteendpoint;
        EndPoint RemotePoint;
        private void button1_Click(object sender, EventArgs e)
        {
            mySocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
           //服务器
            IPAddress ipadd = IPAddress.Parse(this.textBox1.Text);
            IPEndPoint ipend = new IPEndPoint(ipadd, int.Parse(this.textBox2.Text));
            mySocket.Bind(ipend);

            //客户机
            IPAddress ipRemote = IPAddress.Parse(this.textBox4.Text);
            Remoteendpoint = new IPEndPoint(ipadd, int.Parse(this.textBox3.Text));
            RemotePoint=(EndPoint)Remoteendpoint;

            //使用线程处理数据接收

            Thread thread = new Thread(new ThreadStart(Receive));
            thread.IsBackground = true;
            thread.Start();

        }
        public  delegate void MyInvoke(string strRecv) ;
        void Receive()
        {
            //接受数据处理线程
            string msg;
            byte[] data = new byte[1024];
            MyInvoke myI = new MyInvoke(ShowMsg);
            while (true)
            {
                if (mySocket==null||mySocket.Available<1)
                {
                    Thread.Sleep(200);
                    continue;
                }
                //跨线程调用控件
                //接受udp数据报，引用参数RemotePoint获得源地址
                int rlen = mySocket.ReceiveFrom(data, ref RemotePoint);
                msg = Encoding.Default.GetString(data, 0, rlen);
                this.textBox5.BeginInvoke(myI, new object[] { RemotePoint.ToString() + ":" + msg });

            }
        }
        void ShowMsg(string msg)
        {
            //接受数据显示
            this.textBox5.AppendText(msg+"\r\n");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            string msg;
            msg=this.textBox6.Text;
            byte [] data= Encoding.Default.GetBytes(msg);
            mySocket.SendTo(data,data.Length,SocketFlags.None,RemotePoint);
        }
    }
}