新建项目

写接收方

①建立新文件UDPsever

②给项目取名字为UDPsverer

③写入代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;

namespace server
{
    
    class Program
    {
    
        static void Main(string[] args)
        {
    
            UdpClient client = null;
            string receiveString = null;
            byte[] receiveData = null;
            client = new UdpClient(11000);
            //实例化一个远程端点，IP和端口可以随意指定，等调用client.Receive(ref remotePoint)时会将该端点改成真正发送端端点 
            IPEndPoint remotePoint = new IPEndPoint(IPAddress.Any, 0);
            int i = 0;
            while(true)
            {
     
                receiveData = client.Receive(ref remotePoint);//接收数据 
                receiveString = Encoding.Default.GetString(receiveData);
                Console.WriteLine("第" + i + "行" + receiveString);
                i++;
            }
        }
    }
}
}

④运行调试执行

⑤结果

写发送方

① 建立新项目名字为UDPclient

② 输入代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading.Tasks;

namespace UDPclient
{
    
    class Program
    {
    
        static void Main(string[] args)
        {
    
            string sendString = "hello cqjtu！重交物联2018级";//要发送的字符串，如hello cqjtu！重交物联2018级
            byte[] sendData = null;//要发送的字节数组 
            UdpClient client = null;
            IPAddress remoteIP = IPAddress.Parse("10.61.131.59"); //假设发送给这个IP
            int remotePort = 11100;
            IPEndPoint remotePoint = new IPEndPoint(remoteIP, remotePort);//实例化一个远程端点
            client = new UdpClient();
            int i = 0;
            while (i < 50)
            {
    
                sendData = Encoding.Default.GetBytes(sendString);
                client.Send(sendData, sendData.Length, remotePoint);//将数据发送到远程端点 
                Console.WriteLine("第" + i + "行");
                i++;
            }
            client.Close();//关闭连接
            System.Console.ReadKey();//如果没有此句，程序会一闪而过
        }
    }
}

③ 开始调试

发送成功

C#编写一个窗口程序

① 新建项目

②输入项目名

客户端程序
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.Threading.Tasks;
using System.Windows.Forms;
using System.Net.Sockets;

namespace demo
{
    
    public partial class Form1 : Form
    {
    
        public Form1()
        {
    
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
    
            UdpClient udpSender = new UdpClient(0);
            udpSender.Connect("192.168.43.165", 8000);
            string message = textBox1.Text;
            byte[] sendBytes = Encoding.UTF8.GetBytes(message);
            udpSender.Send(sendBytes, sendBytes.Length);
        }

        private void label1_Click(object sender, EventArgs e)
        {
    

        }
    }
}

服务端程序

服务端程序用上面的就行，这里就不写了，接下来是运行结果

wireshark抓包

客户端

这是我抓到的包，源地址是192.168.43.205，目的地址是192.168.43.165，使用协议为UDP，端口号为8000，长度为11字节，数据内容为hello world.
服务端

这是舍友抓到的包，源地址就是192.168.43.205，目的地址为192.168.43.165.内容为hello world，11字节，端口号为11，使用协议为UDP。
参考：
https://blog.csdn.net/weixin_39138071/article/details/79630133?biz_id=102&utm_term=UDP%E4%BB%8B%E7%BB%8D&utm_medium=distribute.pc_search_result.none-task-blog-2_allsobaiduweb~default-0-79630133&spm=1018.2118.3001.4449