如何确定一个IP是否是要联的主机IP呢？

Question

想设计一个任意输入一个IP地址，然后Client端用与之通信。由于输入的IP地址可以不是当时主机的IP，所以此时socketExpection,但是发现通过这个判断时响应速度相当慢，不知道有没有什么快点方法。我现在的这块代码如下：
 Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
                        IPAddress adr = IPAddress.Parse(ip);
                        IPEndPoint ep = new IPEndPoint(adr, 6000);
                
                        try
                        {
                            server.Connect(ep);                        }
                        catch (SocketException se)
                        {
                            
                            if (se.ErrorCode == 10061)
                                MessageBox.Show("Please run host first!");
                            else if (se.ErrorCode == 10060)
                                MessageBox.Show("Can't find the IP address!");
                            else
                                MessageBox.Show(se.Message);
                        }

Answer 1

是这样的，由于不用的用户可能在用的所连接的IP不一样，所以在连接之前让用户输入自己的IP，

Answer 2

 TcpClient tcpClient = new TcpClient();                        bool connflag = false;
                        if (!tcpClient.Connected)
                        {
                            try
                            {
                                IAsyncResult result = tcpClient.BeginConnect(ip, 6000, null, null);                                connflag = result.AsyncWaitHandle.WaitOne(1000, true);//连接超时1秒如果1S内无返回则认为连接失败，connflag为false，如果有返回则为true。
                            }
                            catch (Exception ex)
                            {
                                
                                MessageBox.Show(ex.Message);
                                connflag = false;
                            }
                        }
                        if (!tcpClient.Connected)
                        {
                            MessageBox.Show("An invaliabe IP address!");
                        }
                        else
                        {
                            MessageBox.Show("OK");
                         }

Answer 3

在网上还有看到说用sock.setsockoption，不过我试了没效果
但也有人说那样可以，不清楚，你也可以试试。但上面的代码我正在用，1s后就响应了