Question

我想在c＃程序中接收udp包。组合的几个包的内容是XML状态日志。在一个状态日志完成后重复。见下图。我使用this UDP Broadcast example来获取软件包，端口为53181（见图片）。但该计划没有收到任何东西。有任何想法吗？如何使用收到的包来获取XML数据？

Answer 1

这是我在课堂上制作的通用接收器

public class UdpBroadcastReceiver
{
    private IBroadcastInterpreter _interpreter;
    private volatile bool _shouldReceive = true;

    /// <summary>
    /// Will listen on all ports for udp broadcasts - Will handle input with interpreter
    /// </summary>
    /// <param name="interpreter"></param>
    public UdpBroadcastReceiver(IBroadcastInterpreter interpreter)
    {
        _interpreter = interpreter;
    }

    /// <summary>
    /// Will listen for a broadcast indefinetly. Will lock up your program.
    /// Use Task.Run to start listening. Then you can use StopListening to break the loop.
    /// </summary>
    public void ListenForBroadcast(int port)
    {
        using (UdpClient client = new UdpClient(port))
        {
            IPEndPoint senderEndPoint = new IPEndPoint(IPAddress.Any, 0);
            while (_shouldReceive)
            {
                byte[] receiveBuffer = client.Receive(ref senderEndPoint); // execution will stop and wait for data.
                _interpreter?.HandleBroadcast(receiveBuffer);
            }
        }
    }

    /// <summary>
    /// Breaks the while loop in ListenForBroadcast
    /// </summary>
    public void StopListening()
    {
        _shouldReceive = false;
    }
}

界面

public interface IBroadcastInterpreter
{
    void HandleBroadcast(byte[] input);
}

示例实现可以是：

class WriteToConsole : IBroadcastInterpreter
{
    public void HandleBroadcast(byte[] input)
    {
        string text = Encoding.ASCII.GetString(input);
        Console.WriteLine(text);
    }
}

这是我制作的UDP广播公司，用于广播时间。

class UdpBroadcaster
{

    private int _port;
    private bool shouldRun = true;

    public UdpBroadcaster(int port)
    {
        _port = port;
    }

    public void Stop()
    {
        shouldRun = false;
    }

    public void Start()
    {
        Trace.TraceInformation("Entered start method");
        Task.Run(() =>
                {
                    Trace.TraceInformation("Started task");
                    IPEndPoint serverEndPoint = new IPEndPoint(IPAddress.Broadcast, _port);

                    using (UdpClient client = new UdpClient())
                    {
                        Trace.TraceInformation("Entered using statement");
                        client.EnableBroadcast = true;
                        while(shouldRun)
                        {
                            Trace.TraceInformation("Started while loop");
                            byte[] data = Encoding.ASCII.GetBytes(DateTime.Now.ToString(new CultureInfo("da-dk")));
                            client.Send(data, data.Length, serverEndPoint);
                            Trace.TraceInformation("waiting 5 seconds");
                            Thread.Sleep(5 * 1000);
                        }
                    }
                });
    }

}

创建WriteToConsole类的实例，并将其传递给广播接收器的构造函数。然后，只要接收到广播，它就会使用接口的实现来执行操作。在这种情况下，根据您的要求 - 它只会写入控制台。

c＃接收带xml内容的udp广播包（Windows 7）

1 个答案: