客户端代码

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;
using System.Net.Sockets;
using System.Text;namespace UDPTest
{public partial class Form1 : Form{private UdpClient udpSend;public Form1(){InitializeComponent();}private void button1_Click(object sender, EventArgs e){udpSend = new UdpClient();udpSend.EnableBroadcast = true;//是否可以发送和接收广播IPEndPoint iep = new IPEndPoint(IPAddress.Parse("224.100.0.10"), 8001);byte[] data = Encoding.UTF8.GetBytes(richTextBox1.Text);udpSend.Send(data, data.Length, iep);richTextBox1.Clear();}}
}

服务端代码

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;
using System.Net.Sockets;namespace UDPTest2
{public partial class Form1 : Form{UdpClient udpReceive;public Form1(){InitializeComponent();}private void button1_Click(object sender, EventArgs e){}private void Form1_Load(object sender, EventArgs e){byte[] data = null;udpReceive = new UdpClient(8001);udpReceive.JoinMulticastGroup(IPAddress.Parse("224.100.0.10"), 50);//添加到多路广播组，50为路由器跳数IPEndPoint iep = new IPEndPoint(IPAddress.Any, 0);while (true){data = udpReceive.Receive(ref iep);string str = Encoding.UTF8.GetString(data, 0, data.Length);MessageBox.Show(iep.ToString() + ":" + str);}}}
}