Question

我的程序中的套接字有问题。我正在开发一个嵌入另一个程序的FTP服务器，为了做到这一点，我创建了一个套接字和一个TCPListener。在这种情况下我的问题出现了：
- 我第一次打开连接，如果没有人连接我关闭它，一切都很好;否则，如果有人连接到我的FTP服务器，一切正常; - 如果，在第一次关闭连接并再次打开它之后没有任何人连接，我得到一个SocketException“socket / ip address / port”已经在使用中，我无法再次实例化。
我的功能代码是：

    public void Start()
    {
        ServerStarted = true;

        if (this.authHandler == null)
            this.authHandler = new DefaultAuthHandler();

        if (this.fsHandler == null)
            this.fsHandler = new DefaultFileSystemHandler();

        Socket socketServer = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

        TcpListener listenerServer = new TcpListener(endpoint);
        listenerServer.Start(); // The exception is here at the second time
                                // I open the connection without anybody connected before

        try
        {
            while (ServerStarted)
            {
                socketServer = listenerServer.AcceptSocket();

                try
                {
                    IPEndPoint socketPort = (IPEndPoint)socketServer.RemoteEndPoint;
                    Session session = new Session(socketServer, bufferSize, this.authHandler.Clone(socketPort), this.fsHandler.Clone(socketPort));

                    session.Start();
                    sessions.Add(session);

                    p_HostIPAddress = socketPort.Address;

                    if (p_HostIPAddress != null)
                        HostConnected = true;

                    // Purge old sessions
                    for (int i = sessions.Count - 1; i >= 0; --i)
                    {
                        if (!sessions[i].IsOpen)
                        {
                            sessions.RemoveAt(i);
                            --i;
                        }
                    }
                }
                catch(Exception ex)
                {
                }
            }
        }
        catch (SocketException socketEx)
        {
        }
        finally
        {
            foreach (Session s in sessions)
            {
                s.Stop();
                HostConnected = false;
            }
            TcpSocketListener = null;
        }
    }

我知道在Compact框架中没有Timeout调用，所以，我该怎么做才能避免我的socket仍然在后台打开。哦，对，另外一个额外信息：
我的ftp服务器实际上使用OpenNETCF FTP库

Answer 1

好的，我已经解决了使用SetSocketOption并且我已经改变了一些代码。现在就是这样：

    public void Start()
    {
        ServerStarted = true;

        if (this.authHandler == null)
            this.authHandler = new DefaultAuthHandler();

        if (this.fsHandler == null)
            this.fsHandler = new DefaultFileSystemHandler();

        socketServer = new Socket(AddressFamily.InterNetwork,
                                  SocketType.Stream, 
                                  ProtocolType.Tcp);

        /* Here is the change. In this way I can reuse multiple times the
         * same address without getting the SocketException.*/
        socketServer.SetSocketOption(SocketOptionLevel.Socket,
                                     SocketOptionName.ReuseAddress, 
                                     1);

        Socket handler = null;

        try
        {
            socketServer.Bind(endpoint);
            socketServer.Listen(10);

            while (ServerStarted)
            {
               handler = socketServer.Accept();

                try
                {
                    IPEndPoint socketPort = (IPEndPoint)handler.RemoteEndPoint;
                    Session session = new Session(handler,bufferSize, 
                                         this.authHandler.Clone(socketPort),
                                         this.fsHandler.Clone(socketPort));

                    session.Start();
                    sessions.Add(session);

                    p_HostIPAddress = socketPort.Address;

                    if (p_HostIPAddress != null)
                        HostConnected = true;

                    // Purge old sessions
                    for (int i = sessions.Count - 1; i >= 0; --i)
                    {
                        if (!sessions[i].IsOpen)
                        {
                            sessions.RemoveAt(i);
                            --i;
                        }
                    }
                }
                catch(Exception ex)
                {
                }
            }
        }
        catch (SocketException socketEx)
        {
        }
        finally
        {
            handler.Close();

            foreach (Session s in sessions)
            {
                s.Stop();
                HostConnected = false;
            }
        }
    }

在Compact Framework 2.0中接收超时

1 个答案: