无论我做什么,C#UdpClient.Receive()都不使用多播

时间:2014-04-03 22:43:42

标签: c# network-programming udp multicast udpclient

过去曾试图单独解决这个问题我甚至都不知道,但谷歌搜索不会对我有所帮助,我需要一些建议。我每隔10秒从本地网络上的另一台PC接收UDP数据包,可以在wireshark中看到它们,但应用程序卡在udpClient.Receive()行上。组播组和端口是正确的值,在main()中检查n + 1次。如果您有任何可能有用的想法,请提出建议解决方案。感谢。

(我试图接收服务器的信息,以便应用程序可以自动开始通过TCP进行通信)

class MulticastListener {

    private UdpClient udpClient;
    private IPEndPoint remoteEndPoint;
    IPAddress multicastIP;
    private int port;

    public MulticastListener(ref IPAddress multicastIP, int port) {
        remoteEndPoint = new IPEndPoint(IPAddress.Any, port);

        this.multicastIP = multicastIP;
        this.port = port;
        udpClient = new UdpClient();
        udpClient.Client.Bind(remoteEndPoint);

    }

    public IPEndPoint GetServer() {

        try {
            udpClient.JoinMulticastGroup(multicastIP);
        } catch (ObjectDisposedException e) {
            Console.WriteLine("ERROR: The underlying socket has been closed!");
        } catch (SocketException e) {
            Console.WriteLine("ERROR: An error occurred when accessing the socket!");
        } catch (ArgumentException e) {
            Console.WriteLine("ERROR: The IP address is not compatible with the AddressFamily value that defines the addressing scheme of the socket!");
        }

        Byte[] serverInfoBytes = udpClient.Receive(ref remoteEndPoint);

        Stream stream = new MemoryStream(serverInfoBytes); //receives a serialised IPEndpoint object
        BinaryFormatter formatter = new BinaryFormatter();
        udpClient.Close();
        return (IPEndPoint)formatter.Deserialize(stream);
    }
}

1 个答案:

答案 0 :(得分:0)

正如我评论的那样,您的代码可以100%正常使用。我会检查你发送的是你收到的同一个子网。也许您的发件人未配置到正确的界面?

尝试不同的发件人可能会有所帮助,这是我以前测试的内容:

    static void Main(string[] args)
    {
        //Configuration
        var interfaceIp = IPAddress.Parse("192.168.9.121");
        var interfaceEndPoint = new IPEndPoint(interfaceIp, 60001);
        var multicastIp = IPAddress.Parse("230.230.230.230");
        var multicastEndPoint = new IPEndPoint(multicastIp, 60001);

        //initialize the socket
        var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
        socket.ExclusiveAddressUse = false;
        socket.MulticastLoopback = false;
        socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, 1);
        MulticastOption option = new MulticastOption(multicastEndPoint.Address, interfaceIp);
        socket.SetSocketOption(SocketOptionLevel.IP, SocketOptionName.AddMembership, option);

        //bind on a network interface
        socket.Bind(interfaceEndPoint);

        //initialize args for sending packet on the multicast channel
        var sockArgs = new SocketAsyncEventArgs();
        sockArgs.RemoteEndPoint = multicastEndPoint;
        sockArgs.SetBuffer(new byte[1234], 0, 1234);

        //send an empty packet of size 1234 every 3 seconds
        while (true)
        {
            socket.SendToAsync(sockArgs);
            Thread.Sleep(3000);
        }
    }