Question

我正在研究使用异步客户端 - 服务器套接字的MSDN示例代码。我理解在建立客户端的新连接时这是怎么回事。

但是，如果客户端已经连接，并希望将一些新数据传递给服务器（或其他客户端），该怎么办？

这是我到目前为止所做的：

public partial class Form1 : Form
{
    AsynchronousClient ac;
    public Form1()
    {
        InitializeComponent();            
    }

    private void buttonLogin_Click(object sender, EventArgs e)
    {
        buttonLogin.Enabled = false;
        new Thread(new ThreadStart(CreatingConnection)).Start();
    }

    private void CreatingConnection()
    {
        ac = new AsynchronousClient();
        ac.SendingMessage += (msg) => AC_SendingMassage(msg);
        ac.StartClient();
    }

    private void AC_SendingMassage(string message)
    {
        listBox1.Invoke((MethodInvoker)delegate { listBox1.Items.Add(message); });
    }

    private void buttonData_Click(object sender, EventArgs e)
    {
        string message = textBox1.Text;
        //TODO:
        //how to send data from here (including whats in textBox)??
    }
}

这是msdn的例子中的代码（2个类）（仅适用于客户端）：

public class StateObject
{
    public Socket workSocket = null;
    public const int BufferSize = 256;
    public byte[] buffer = new byte[BufferSize];
    public StringBuilder sb = new StringBuilder();
}

public class AsynchronousClient
{
    public event Action<string> SendingMessage;
    // The port number for the remote device.
    private const int port = 11000;

    // ManualResetEvent instances signal completion.
    private static ManualResetEvent connectDone = new ManualResetEvent(false);
    private static ManualResetEvent sendDone = new ManualResetEvent(false);
    private static ManualResetEvent receiveDone = new ManualResetEvent(false);

    // The response from the remote device.
    private string response;

    public void StartClient()
    {
        // Connect to a remote device.
        try
        {
            // Establish the remote endpoint for the socket.
            string ip = "192.168.1.101";
            IPAddress ipAddress = IPAddress.Parse(ip);
            IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);

            // Create a TCP/IP socket.
            Socket client = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            // Connect to the remote endpoint.
            client.BeginConnect(remoteEP, new AsyncCallback(ConnectCallback), client);
            connectDone.WaitOne();

            // Send test data to the remote device.
            Send(client, "This is a test<EOF>");
            sendDone.WaitOne();

            // Receive the response from the remote device.
            Receive(client);
            receiveDone.WaitOne();

            // Write the response to the console.
            SendingMessage(string.Format("Response received : {0}", response));

            // Release the socket.
            client.Shutdown(SocketShutdown.Both);
            client.Close();
        }
        catch (Exception e)
        {
            SendingMessage(e.Message);
        }
    }

    private void ConnectCallback(IAsyncResult ar)
    {
        try
        {
            // Retrieve the socket from the state object.
            Socket client = (Socket)ar.AsyncState;

            // Complete the connection.
            client.EndConnect(ar);

            //Console.WriteLine("Socket connected to {0}", client.RemoteEndPoint.ToString());
            SendingMessage(string.Format("Socket connected to {0}", client.RemoteEndPoint.ToString()));

            // Signal that the connection has been made.
            connectDone.Set();
        }
        catch (Exception e)
        {
            //Console.WriteLine(e.ToString());
            SendingMessage(e.Message);
        }
    }

    private void Receive(Socket client)
    {
        try
        {
            // Create the state object.
            StateObject state = new StateObject();
            state.workSocket = client;

            // Begin receiving the data from the remote device.
            client.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ReceiveCallback), state);
        }
        catch (Exception e)
        {
            SendingMessage(e.Message);
        }
    }

    private void ReceiveCallback(IAsyncResult ar)
    {
        try
        {
            // Retrieve the state object and the client socket from the asynchronous state object.
            StateObject state = (StateObject)ar.AsyncState;
            Socket client = state.workSocket;

            // Read data from the remote device.
            int bytesRead = client.EndReceive(ar);

            if (bytesRead > 0)
            {
                // There might be more data, so store the data received so far.
                state.sb.Append(Encoding.ASCII.GetString(state.buffer, 0, bytesRead));

                // Get the rest of the data.
                client.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ReceiveCallback), state);
            }
            else
            {
                // All the data has arrived; put it in response.
                if (state.sb.Length > 1)
                {
                    response = state.sb.ToString();
                }
                // Signal that all bytes have been received.
                receiveDone.Set();
            }
        }
        catch (Exception e)
        {
            SendingMessage(e.Message);
        }
    }

    public void Send(Socket client, string data)
    {
        // Convert the string data to byte data using ASCII encoding.
        byte[] byteData = Encoding.ASCII.GetBytes(data);

        // Begin sending the data to the remote device.
        client.BeginSend(byteData, 0, byteData.Length, 0, new AsyncCallback(SendCallback), client);
    }

    private void SendCallback(IAsyncResult ar)
    {
        try
        {
            // Retrieve the socket from the state object.
            Socket client = (Socket)ar.AsyncState;

            // Complete sending the data to the remote device.
            int bytesSent = client.EndSend(ar);
            //Console.WriteLine("Sent {0} bytes to server.", bytesSent);
            SendingMessage(string.Format("Sent {0} bytes to server.", bytesSent));
            // Signal that all bytes have been sent.
            sendDone.Set();
        }
        catch (Exception e)
        {
            SendingMessage(e.Message);
        }
    }
}

- 有一个buttonData的click事件，我想用它来将数据传递给服务器。我想知道在连接时调用哪种方法来传递新数据。

Answer 1

您将使用Send方法发送数据。但是，这个示例代码看起来真的只是为了向您展示一些异步方法是如何工作的。 StartClient方法关闭所有内容，这可能不是您想要做的。您可能需要编写自己的代码才能执行此操作。

异步客户端套接字：如何将其他数据传递给服务器？

1 个答案: