UDP聊天

界面如下图，消息展示框，发送地址栏，和发送消息栏

打开程序会起一个线程接收消息。发送

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 UdpChat
{
    public partial class Form1 : Form
    {
        private UdpClient sendClient;
        private UdpClient receiveClient;

        Thread threadReceive, threadSend;

        private int receivePort = 2158;
        private int sendPort = 2675;

        private string LocalIp
        {
            get 
            {
                IPAddress[] ips = Dns.GetHostAddresses("");
                return ips[2].ToString();
            }
        }

        public Form1()
        {
            InitializeComponent();

            this.tbPort.Text = receivePort.ToString();
            receiveClient = new UdpClient(receivePort);//new IPEndPoint(IPAddress.Parse(LocalIp),receivePort));
            threadReceive = new Thread(new ThreadStart(ReceiveMessage));
            threadReceive.Start();
        }

        #region 接收消息

        private void ReceiveMessage()
        {
            IPEndPoint endPoint = new IPEndPoint(IPAddress.Any, 0);
            while (true)
            {
                try
                {
                    // 关闭进程时此时会产生异常
                    byte[] receiveBuffer = receiveClient.Receive(ref endPoint);
                    string message = endPoint.Address +"："+ System.Text.Encoding.UTF8.GetString(receiveBuffer);
                    this.Invoke(new ListBoxAddMsgHandler(ListBoxAddMsg), new object[] { message });
                }
                catch 
                {
                    threadSend.Abort();
                    break; 
                }
            }
        }

        private delegate void ListBoxAddMsgHandler(object msg);
        /// <summary>
        /// 添加信息
        /// </summary>
        /// <param name="msg"></param>
        private void ListBoxAddMsg(object msg)
        {
            listBox1.Items.Add(msg);
        }

        #endregion

        #region 发送消息

        private void btnSend_Click(object sender, EventArgs e)
        {
            // 匿名模式(套接字绑定的端口由系统随机分配)
            sendClient = new UdpClient(0);//new IPEndPoint(IPAddress.Parse(LocalIp), sendPort));
            threadSend = new Thread(SendMsg);
            threadSend.Start(tbMsg.Text);
        }

        private void SendMsg(object msg)
        {
            string message = msg.ToString();
            byte[] msgBuffer = System.Text.Encoding.UTF8.GetBytes(message);
            try
            {
                IPEndPoint remoteIp=new IPEndPoint(IPAddress.Parse(tbIP.Text), int.Parse(tbPort.Text));
                sendClient.Send(msgBuffer, msgBuffer.Length,remoteIp);
            }
            catch (Exception ex) { MessageBox.Show(ex.Message); }
            sendClient.Close();
            this.Invoke(new CliearTextBoxHandler(ClearTextBox));
            threadSend.Abort();
        }

        private delegate void CliearTextBoxHandler();

        private void ClearTextBox()
        {
            this.tbMsg.Text = string.Empty;
        }

        #endregion
    }
}