C# 提示：由于目标机积极拒绝，无法连接。。。

[yanjingshe22]

小弟最近想写了监控端，就监控客户端是否开启。

小弟的设想是，开了服务端后，就绑定本机的IP和一个端口。客户端开启的时候就尝试对这个IP和端口进行连接。

现在出现的问题是，抛了个异常，异常的信息是：由于目标机积极拒绝，无法连接。。。。

小弟的服务端的socket代码如下：
class ServerSocket
{
#region 私有字段定义和构造函数
private const int NUM = 80;
private int reciv = 0;
//设定IP值
static IPAddress ip = IPAddress.Parse("127.0.0.1");
//设定端口值
static int port = 5000;
//持有客户端socket对象的引用
public Socket client { set; get; }
IPEndPoint ep = new IPEndPoint(ip, port);
public ServerSocket()
{
client = null;
}

#endregion

TcpListener listner = new TcpListener(ip, port);

//开始监听

public void ClientListner()
{
Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
server.SetSocketOption(SocketOptionLevel.Socket,SocketOptionName.ReuseAddress,true);
//server.Bind(ep);

listner.Start();
}
}

小弟的客户端代码如下：
y
{
Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
IPAddress ip = IPAddress.Parse("127.0.0.1");
IPEndPoint ep = new IPEndPoint(ip, 5000);

server.Connect(ep);

byte[] buffer = new byte[255];
int recv = 0;
string data = null;

recv = server.Receive(buffer);

if (recv > 0)
{
Console.WriteLine("连接上。。。。");
Console.WriteLine("准备接受数据");

data = Encoding.ASCII.GetString(buffer, 0, recv);
Console.WriteLine(data);

while (true)
{
string input;
input = Console.ReadLine();
if (input == "exit")
{
break;
}
}
server.Shutdown(SocketShutdown.Both);
server.Close();
}
}
catch (SocketException e)
{
Console.WriteLine(e.Message);
Console.ReadLine();
}

忘高手指点指点。谢谢！

[wenbin]

ProtocolType.TCP
你试下

[yanjingshe22]

我试过了，还是不行。

我找了下原因，好像是那个端口根本就没开起来。不知道为什么没开起来。求解。

[wuyq11]

采用TCP/udp协议进行连接,检查windows防火墙是否开放相应SocketTCP/udp端口
地址是否正确
资源释放

[dancingbit]

你的Server只是执行了Start，只是开始了侦听，然而还需要AcceptSocket或AcceptTcpClient方法来接受来自客户端的连接请求。

[wenbin]

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

class MyTcpListener
{
  public static void Main()
  { 
    TcpListener server=null;   
    try
    {
      // Set the TcpListener on port 13000.
      Int32 port = 13000;
      IPAddress localAddr = IPAddress.Parse("127.0.0.1");

      // TcpListener server = new TcpListener(port);
      server = new TcpListener(localAddr, port);

      // Start listening for client requests.
      server.Start();

      // Buffer for reading data
      Byte[] bytes = new Byte[256];
      String data = null;

      // Enter the listening loop.
      while(true) 
      {
        Console.Write("Waiting for a connection... ");

        // Perform a blocking call to accept requests.
        // You could also user server.AcceptSocket() here.
        TcpClient client = server.AcceptTcpClient();            
        Console.WriteLine("Connected!");

        data = null;

        // Get a stream object for reading and writing
        NetworkStream stream = client.GetStream();

        int i;

        // Loop to receive all the data sent by the client.
        while((i = stream.Read(bytes, 0, bytes.Length))!=0) 
        {   
          // Translate data bytes to a ASCII string.
          data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
          Console.WriteLine("Received: {0}", data);

          // Process the data sent by the client.
          data = data.ToUpper();

          byte[] msg = System.Text.Encoding.ASCII.GetBytes(data);

          // Send back a response.
          stream.Write(msg, 0, msg.Length);
          Console.WriteLine("Sent: {0}", data);            
        }

        // Shutdown and end connection
        client.Close();
      }
    }
    catch(SocketException e)
    {
      Console.WriteLine("SocketException: {0}", e);
    }
    finally
    {
       // Stop listening for new clients.
       server.Stop();
    }


    Console.WriteLine("\nHit enter to continue...");
    Console.Read();
  }   
}

微软的代码，你试下，地址和端口修改下

[yanjingshe22]

谢谢各位的指点，程序正确解决了。现在散分，谢谢大家。

[cqqinqin]

看看，正需要