Question

我有一个套接字客户端应用程序，它“不允许发送或接收数据的请求，因为套接字未连接......”

public void Connect()
    {
        if (mPort == 0) throw new Exception("No ip set to client.");
        mSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        mSocket.BeginConnect(mHost, mPort, new AsyncCallback(OnConnected), mSocket);
        mReceiveBuffer = new byte[MAX_RECEIVE_BUFFER];
    }


private void OnConnected(IAsyncResult ar)
    {
        try
        {
            mSocket.EndConnect(ar);
            BeginReceive();
        }
        catch
        {
            Disconnect();
        }
    }

        private void BeginReceive()
    {
        mSocket.BeginReceive(inBuffer, 0, 300, SocketFlags.None, new AsyncCallback(onDataRecieve), mSocket);
    }

错误抛出mSocket.BeginReceive。这只发生在Windows XP上。有谁知道为什么会这样？

Answer 1

您没有检查结果。连接尝试失败，超时后OnConnect将触发。

这是一个完整的工作示例。对我来说工作正常，应该适合你。你会注意到我正在检查我是否真的连接了，并且我保留了完成所有工作的线程。

public class Program
{
    static void Main(string[] args)
    {
        AsyncSocketTest test = new AsyncSocketTest();

        test.SocketTest();
    }
}

public class AsyncSocketTest
{
    private Socket socket;
    private byte[] buffer;
    private volatile bool keepRunning;

    public void SocketTest()
    {
        Console.Out.WriteLine("Starting connect...");
        Console.Out.Flush();

        buffer = new byte[65536];

        keepRunning = true;

        // connect to antiduh.com's web server
        socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        socket.BeginConnect(IPAddress.Parse("129.21.49.41"), 80, new AsyncCallback(OnConnect), null);

        // Keep the main thread alive while all of the async requests run.
        while (keepRunning) { Thread.Sleep(500); }

        Console.Out.WriteLine("Quitting.");
        Console.Out.Flush();
    }

    private void OnConnect(IAsyncResult result)
    {
        try
        {
            if (result.IsCompleted == false)
            {
                Console.Out.WriteLine("OnConnect got incomplete result: " + result);
            }
            else
            {
                socket.EndConnect(result);

                if (result.IsCompleted == false)
                {
                    Console.Out.WriteLine("OnConnect got incomplete result: " + result);
                }
                else
                {

                    Console.Out.WriteLine("Sending...");
                    byte[] requestBytes;
                    string requestString =
                        "GET / HTTP/1.1\n" +
                        "Host: antiduh.com\n" +
                        "\n";

                    requestBytes = Encoding.ASCII.GetBytes(requestString);
                    socket.Send(requestBytes);

                    Console.Out.WriteLine("Starting receive...");
                    socket.BeginReceive(
                        buffer, 
                        0, 
                        buffer.Length, 
                        SocketFlags.None, 
                        new AsyncCallback(OnReceive),
                        null
                    );
                }
            }
        }
        catch (Exception e)
        {
            Console.Out.WriteLine("Caught exception in OnConnect: " + e);
        }
        finally
        {
            Console.Out.Flush();
        }
    }

    private void OnReceive(IAsyncResult result)
    {
        int received = socket.EndReceive(result);
        string responseStr;

        Console.Out.WriteLine("Received data: Length: {0}. Data: \r\n\r\n", received);
        Console.Out.Flush();

        responseStr = Encoding.ASCII.GetString(buffer, 0, received);

        Console.Out.WriteLine(responseStr);
        Console.Out.Flush();

        socket.Close();
        keepRunning = false;
    }
}

输出：

Starting connect...
Sending...
Starting receive...
Received data: Length: 1137. Data: 


HTTP/1.1 200 OK
Date: Tue, 02 Jul 2013 12:58:19 GMT
Server: Apache/2.2.24 (FreeBSD) PHP/5.4.16 SVN/1.8.0 mod_ssl/2.2.24 OpenSSL/1.0.1e DAV/2
Last-Modified: Tue, 11 Jul 2006 05:03:19 GMT
ETag: "352-418473fcd33c0"
Accept-Ranges: bytes
Content-Length: 850
Content-Type: text/html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>welcome to antiduh</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css">
<!--
body {
    background-color: #6666CC;
}
-->
</style></head>

<body>
<img src="index.gif" alt="index of steak" width="912" height="528" border="0" align="middle" usemap="#Map">
<map name="Map">
  <area shape="rect" coords="234,97,392,132" href="about.htm" alt="about">
  <area shape="rect" coords="691,150,846,186" href="projects.htm" alt="projects">
  <area shape="rect" coords="740,363,884,399" href="links.htm" alt="links">
  <area shape="rect" coords="423,478,562,511" href="misc.htm" alt="misc">
  <area shape="rect" coords="37,292,175,324" href="resume.htm" alt="resume">
</map>
</body>
</html>

Quitting.

Windows XP套接字错误

1 个答案: