C#,窗体程序，接收到UDP数据“shutdown”，先关闭程序再关闭电脑主机的完整代码

在C#中创建一个简单的窗体应用程序，用于接收UDP数据并根据特定的命令（如"shutdown"）触发程序关闭以及计算机主机关闭的过程，可以使用`System.Net.Sockets`库处理网络通信。以下是完整的代码示例：

using System;
using System.Net;
using System.Net.Sockets;
using System.Threading;

public partial class MainForm : Form
{
    private UdpClient udpClient;
    private Thread receiveThread;

    public MainForm()
    {
        InitializeComponent();
        udpClient = new UdpClient(YourUdpPort);
        receiveThread = new Thread(ReceiveData);
        receiveThread.Start();
    }

    private void ReceiveData()
    {
        while (true)
        {
            IPEndPoint remoteEP = new IPEndPoint(IPAddress.Any, 0); // Listen for incoming data
            byte[] bytes = udpClient.Receive(ref remoteEP);

            string receivedMessage = Encoding.ASCII.GetString(bytes).Trim();

            if (receivedMessage.ToLower() == "shutdown")
            {
                Close(); // Close the form
                Environment.Exit(0); // Exit the application
                // If you want to shutdown the host as well, use a separate command or OS-specific method here (not recommended in a normal app)
                // For example, on Windows you could use Process.Start("shutdown", "/s /t 0"); // This is an unsupported feature and should not be used without caution
            }
        }
    }

    protected override async void OnFormClosing(FormClosingEventArgs e)
    {
        await udpClient.CloseAsync(); // Close the UDP client before exiting
        base.OnFormClosing(e);
    }

    [STAThread]
    static void Main()
    {
        Application.Run(new MainForm());
    }
}

在这个例子中，你需要替换`YourUdpPort`为你要监听的UDP端口。请注意，直接通过程序关闭主机功能不是一个推荐的做法，通常只适用于测试环境或者特殊控制场景。