Question

我正在处理简单的客户端服务器应用程序，它就像聊天Messenger一样。我正在使用Client Server方法。我的应用程序在LAN局域网上工作正常。但是当它尝试通信以切断局域网外。然后没有对客户的回复。虽然我知道服务器IP地址（通过外部手段）使用宽带连接并驻留在WAN上。我想我无法解析IP地址，或代理问题发生。有人可以帮帮我吗？问候！ Sm.Abdullah

//
/*   Server Program    */

using System;
using System.Text;
using System.Net;
using System.Net.Sockets;

public class serv {
    public static void Main() {
    try {
        IPAddress ipAd = IPAddress.Parse("172.21.5.99");
         // use local m/c IP address, and 
         // use the same in the client

/* Initializes the Listener */
        TcpListener myList=new TcpListener(ipAd,8001);

/* Start Listeneting at the specified port */        
        myList.Start();

        Console.WriteLine("The server is running at port 8001...");    
        Console.WriteLine("The local End point is  :" + 
                          myList.LocalEndpoint );
        Console.WriteLine("Waiting for a connection.....");

        Socket s=myList.AcceptSocket();
        Console.WriteLine("Connection accepted from " + s.RemoteEndPoint);

        byte[] b=new byte[100];
        int k=s.Receive(b);
        Console.WriteLine("Recieved...");
        for (int i=0;i<k;i++)
            Console.Write(Convert.ToChar(b[i]));

        ASCIIEncoding asen=new ASCIIEncoding();
        s.Send(asen.GetBytes("The string was recieved by the server."));
        Console.WriteLine("\nSent Acknowledgement");
/* clean up */            
        s.Close();
        myList.Stop();

    }
    catch (Exception e) {
        Console.WriteLine("Error..... " + e.StackTrace);
    }    
    }

}

---------------------------------------------------------------------------

/*       Client Program      */

using System;
using System.IO;
using System.Net;
using System.Text;
using System.Net.Sockets;


public class clnt {

    public static void Main() {

        try {
            TcpClient tcpclnt = new TcpClient();
            Console.WriteLine("Connecting.....");
            // here is local ip.. 
            // if i replace it with WAN IP it does not communicate.
            tcpclnt.Connect("172.21.5.99",8001);
            // use the ipaddress as in the server program

            Console.WriteLine("Connected");
            Console.Write("Enter the string to be transmitted : ");

            String str=Console.ReadLine();
            Stream stm = tcpclnt.GetStream();

            ASCIIEncoding asen= new ASCIIEncoding();
            byte[] ba=asen.GetBytes(str);
            Console.WriteLine("Transmitting.....");

            stm.Write(ba,0,ba.Length);

            byte[] bb=new byte[100];
            int k=stm.Read(bb,0,100);

            for (int i=0;i<k;i++)
                Console.Write(Convert.ToChar(bb[i]));

            tcpclnt.Close();
        }

        catch (Exception e) {
            Console.WriteLine("Error..... " + e.StackTrace);
        }
    }

}

Answer 1

您检查过防火墙/路由器吗？

大部分时间未经请求的传入连接都被驳回，并且会失败，因为它们可能在起源和性质上都是恶意的。

然而，您可以通过查看NAT遍历来解决其中一些问题

请参阅：tcp client to communicate with server present in different network (NAT issue)

无法使用客户端服务器方法通过WAN连接服务器？

1 个答案: