Question

C#编程 TCP/IP通信 问题

为什么客户端和主机连接的时候总是出现主机积极拒绝。即使我把防火墙和杀毒软件都关了，还是会出现。并且端口什么的都是正常的。请大家指点一下。提供可以实现客服端和主机的程序也可以。提供程序的时候请注明重要代码的意思。

Answer 1

服务端

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Sockets;

namespace SocketSer
{

class Program
{
[STAThread]

static void Main(string[] args)
{
int recv;
byte[] data = new byte[1024];
IPEndPoint ipep = new IPEndPoint(IPAddress.Any, 9050);
Socket newsock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
newsock.Bind(ipep);
newsock.Listen(10);
Console.WriteLine("等待客户端连接中。。。");
Socket client = newsock.Accept();
IPEndPoint clientip = (IPEndPoint)client.RemoteEndPoint;
Console.WriteLine("已连接的客户端：" + clientip.Address + ",端口" + clientip.Port);
string welcome="welcome here!";
data=Encoding.ASCII.GetBytes(welcome);
client.Send(data,data.Length,SocketFlags.None);//发送信息
while(true)
{//用死循环来不断的从客户端获取信息
data=new byte[1024];
recv=client.Receive(data);
Console.WriteLine("recv="+recv);
if (recv==0)//当信息长度为0，说明客户端连接断开
break;
Console.WriteLine(Encoding.ASCII.GetString(data,0,recv));
client.Send(data,recv,SocketFlags.None);
}
Console.WriteLine("已断开从"+clientip.Address+"的连接。" );
client.Close();
newsock.Close();

}
}
}

客户端

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Sockets;

namespace SocketCli
{
class Program
{
[STAThread]
static void Main(string[] args)
{
//
// TODO: 在此处添加代码以启动应用程序
//
byte[] data = new byte[1024];
Socket newclient=new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);
//Console.Write("请输入服务器");
//string ipadd=Console.ReadLine();
//Console.WriteLine();
//Console.Write("please input the server port:");
//int port=Convert.ToInt32(Console.ReadLine());
IPEndPoint ie=new IPEndPoint(IPAddress.Parse("192.168.1.2"),9050);//服务器的IP和端口
try
{
//因为客户端只是用来向特定的服务器发送信息，所以不需要绑定本机的IP和端口。不需要监听。
newclient.Connect(ie);
}
catch(SocketException e)
{
Console.WriteLine("未连接服务器");
Console.WriteLine(e.ToString());
Console.ReadLine();
return;
}
int recv = newclient.Receive(data);
string stringdata=Encoding.ASCII.GetString(data,0,recv);
Console.WriteLine(stringdata);
while(true)
{
string input=Console.ReadLine();
if(input=="exit")
break;
newclient.Send(Encoding.ASCII.GetBytes(input));
data=new byte[1024];
recv=newclient.Receive(data);
stringdata=Encoding.ASCII.GetString(data,0,recv);
Console.WriteLine(stringdata);
}
Console.WriteLine("disconnect from sercer");
newclient.Shutdown(SocketShutdown.Both);
newclient.Close();

}
}
}