如何设置Socket.ConnectAsync的超时时间？

Question

我一直在阅读关于如何检查局域网上特定端口上的所有监听服务器，最后我写了一些代码，它可以工作，因为我想要的。
我使用System.Threading.Tasks.Parallel尽可能快地连接到所有254个IP地址
ex： 192.168.1。 - 192.168.1。

我需要做的是为这些连接尝试超时，因为它需要约15-20秒打印：“连接失败”，当它失败..所以我该怎么办呢？

这里的客户端代码：

static void Main(string[] args) 
    { 
     Console.WriteLine("Connecting to IP addresses has started. \n"); 

     Parallel.For(1, 255, i => 
     { 
      Connect("192.168.1." + i); 
     }); 
     Console.ReadLine(); 
    } 

    private static void Connect(string ipAdd) 
    { 
     Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); 
     SocketAsyncEventArgs e = new SocketAsyncEventArgs(); 
     IPEndPoint ipEnd = new IPEndPoint(IPAddress.Parse(ipAdd), 9990); 
     e.RemoteEndPoint = ipEnd; 
     e.UserToken = s; 
     e.Completed += new EventHandler<SocketAsyncEventArgs>(e_Completed); 
     Console.WriteLine("Trying to connect to : " + ipEnd); 
     s.ConnectAsync(e); 
    } 
    private static void e_Completed(object sender, SocketAsyncEventArgs e) 
    { 
     if (e.ConnectSocket != null) 
     { 
      StreamReader sr = new StreamReader(new NetworkStream(e.ConnectSocket)); 
      Console.WriteLine("Connection Established : " + e.RemoteEndPoint + " PC NAME : " + sr.ReadLine()); 
     } 
     else 
     { 
      Console.WriteLine("Connection Failed : " + e.RemoteEndPoint); 
     } 
    } 

服务器代码：

static void Main(string[] args) 
    { 
     Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); 
     IPEndPoint ep = new IPEndPoint(IPAddress.Any,9990); 
     server.Bind(ep); 
     server.Listen(100); 
     Socket client = server.Accept(); 
     NetworkStream stream = new NetworkStream(client); 
     StreamWriter sw = new StreamWriter(stream) 
     sw.WriteLine(System.Environment.MachineName); 
     sw.Flush(); 
     sw.Dispose(); 
     stream.Dispose(); 
     client.Dispose(); 
     server.Dispose(); 
    } 

如果有使得它更告诉我任何提示或通知。我正在使用[.Net 4.0]套接字TCP
对不起，我的英语不好，在此先感谢..

Answer 1

我已经想出了一个解决方案。
首先创建的套接字添加类型的列表的SocketAsyncEventArgs或插座或
的类型 然后使用System.Timers.Timer以关闭所有挂起连接，并且当计时器滴答后的连接的一个，其是在5秒后。 （timer.Interval = 5000）。

客户端代码：

//I've changed my console application to Winform 
    public ServerDiscovery() 
    { 
     InitializeComponent(); 
     timer.Elapsed += timer_tick; 
    } 

    System.Timers.Timer timer = new System.Timers.Timer(5000); 
    List<SocketAsyncEventArgs> list = new List<SocketAsyncEventArgs>(); 

    private void btnRefresh_Click(object sender, EventArgs e) 
    { 
     timer.Start(); 
     Parallel.For(1, 255, (i, loopState) => 
     { 
      ConnectTo("192.168.1." + i); 
     }); 
    } 

    private void ConnectTo(string ipAdd) 
    { 
     Socket s = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); 
     SocketAsyncEventArgs e = new SocketAsyncEventArgs(); 
     e.RemoteEndPoint = new IPEndPoint(IPAddress.Parse(ipAdd), 9990); 
     e.UserToken = s; 
     e.Completed += new EventHandler<SocketAsyncEventArgs>(e_Completed); 
     list.Add(e);  // Add to a list so we dispose all the sockets when the timer ticks. 
     s.ConnectAsync(e); 
    } 

    private void e_Completed(object sender, SocketAsyncEventArgs e) 
    { 
     if (e.ConnectSocket != null)  //if there's a connection Add its info to a listview 
     { 
      StreamReader sr = new StreamReader(new NetworkStream(e.ConnectSocket)); 
      ListViewItem item = new ListViewItem(); 
      item.Text = sr.ReadLine(); 
      item.SubItems.Add(((IPEndPoint)e.RemoteEndPoint).Address.ToString()); 
      item.SubItems.Add("Online"); 
      AddServer(item); 
     } 
    } 

    delegate void AddItem(ListViewItem item); 
    private void AddServer(ListViewItem item) 
    { 
     if (InvokeRequired) 
     { 
      Invoke(new AddItem(AddServer), item); 
      return; 
     } 
     listServer.Items.Add(item); 
    } 

    private void timer_tick(object sender, EventArgs e) 
    { 
     timer.Stop(); 
     foreach (var s in list) 
     { 
      ((Socket)s.UserToken).Dispose();  //disposing all sockets that's pending or connected. 
     } 
    } 

Answer 2

我找不到任何内置的超时机制。您应该设置一个计时器并在触发时中止连接。类似的东西：How to configure socket connect timeout