6

我还在努力改进我之前写的东西。现在我遇到了接收数据的问题。我有一个程序，我用它使用 tcpClient 将字符串发送到我正在侦听指定端口的程序。它工作正常，所以我决定再发送一次数据

public static void receiveThread()
{
    while (true)
    {
        TcpListener tcpListener = new TcpListener(IPAddress.Any, port);
        tcpListener.Start();

        Console.WriteLine("Waiting for connection...");

        TcpClient tcpClient = tcpListener.AcceptTcpClient();

        Console.WriteLine("Connected with {0}", tcpClient.Client.RemoteEndPoint);

        while (!(tcpClient.Client.Poll(20, SelectMode.SelectRead)))
        {
            NetworkStream networkStream = tcpClient.GetStream();
            StreamReader streamReader = new StreamReader(networkStream);

            data = streamReader.ReadLine();

            if (data != null)
            {
                Console.WriteLine("Received data: {0}", data);
                send(data); // Here Im using send Method
            }
        }
        Console.WriteLine("Dissconnected...\n");
        tcpListener.Stop();
    }
}

/// <summary>
/// Sending data
/// </summary>
/// <param name="data">Data to send</param>
public static void send(string data)
{
    TcpClient tcpClient = new TcpClient();
    try
    {
        tcpClient.Connect(ipAddress, sendPort);
        Console.WriteLine("Connected with {0}", tcpClient.Client.RemoteEndPoint);
    }
    catch (Exception e)
    {
        Console.WriteLine(e);
    }
    if (tcpClient.Connected)
    {
        NetworkStream networkStream = tcpClient.GetStream();
        StreamWriter streamWriter = new StreamWriter(networkStream);
        Console.WriteLine("Messege {0} to {1}", data, tcpClient.Client.RemoteEndPoint);
        streamWriter.WriteLine(data);
        streamWriter.Flush();
        tcpClient.Close();
    }
}

有时它工作得很好，但更多时候，我们称它为接收器，无法得到我试图发送的东西。我真的不知道它有什么问题。看起来发送方法可能有问题。这是接收器输出的示例

Waiting for connection...
Connected with 127.0.0.1:52449
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52450
Received data: qweqwe
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52451
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52452
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52453
Received data: zxczx
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52454
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52455
Received data: aasd
Dissconnected...

Waiting for connection...
Connected with 127.0.0.1:52457
Received data: www
Dissconnected...
4

2 回答 2

6

这里有几个问题：

  1. StreamReader有一个 4kB 的缓冲区，并会在第一次调用ReadLine(). 结果是您可能在 StreamReader 中有数据，并在没有更多可用数据时进入 Poll()，因为它已经被读取。
  2. Poll()需要微秒。等待传入数据的0.02 毫秒可能会返回 false，除非数据在您调用之前就在那里Poll()。
  3. 您在每次迭代中创建一个新的 StreamReader，这可能会丢弃前一次中已读取的数据。

如果您只是要阅读行并想要超时和 a StreamReader，我会执行以下操作：

delegate string ReadLineDelegate ();
...
using (NetworkStream networkStream = tcpClient.GetStream()) {
    StreamReader reader = new StreamReader(networkStream);
    ReadLineDelegate rl = new ReadLineDelegate (reader.ReadLine);
    while (true) {
        IAsyncResult ares = rl.BeginInvoke (null, null);
        if (ares.AsyncWaitHandle.WaitOne (100) == false)
            break; // stop after waiting 100ms
        string str = rl.EndInvoke (ares);
        if (str != null) {
            Console.WriteLine ("Received: {0}", str);
            send (str);
        } 
    }
}
于 2009-12-03T01:00:16.133 回答
1

在追鬼之前，确保数据确实存在于流中。如果总是有数据，我们可以解决问题，但是从逻辑上看，它看起来好像流要么被清空，要么上面没有数据。

于 2009-12-03T00:12:04.593 回答