好的，所以我的代码中有一个套接字连接导致了问题。它连接然后很快断开连接。它在“connections ++”之后断开连接线。有什么想法吗？
根据以下表格要求提供所有代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
namespace Middleware
{
public partial class Middleware : Form
{
//variables
private Socket server;
private Socket remoteclient;
private Socket clientreturn;
private Socket serversync;
private byte[] data = new byte[1024];
private byte[] datars = new byte[1024];
private int connections = 0;
public Middleware()
{
InitializeComponent();
Control.CheckForIllegalCrossThreadCalls = false;
}
private void Middleware_Load(object sender, EventArgs e)
{
}
void OnConnectedRemote(IAsyncResult result)
{
try
{
remoteclient.EndConnect(result);
}
catch
{
remoteclient.Close();
}
}
void OnConnected(IAsyncResult result)
{
Socket client = server.EndAccept(result);
connections++;
server.BeginAccept(new AsyncCallback(OnConnected), null);
try
{
txtStatus.Text = "" + connections;
byte[] message = Encoding.ASCII.GetBytes("Welcome to my server");
client.BeginSend(message, 0, message.Length, SocketFlags.None, new AsyncCallback(OnDataSent), client);
}
catch
{
client.Close();
}
}
void OnConnectedSync(IAsyncResult result)
{
Socket sync = serversync.EndAccept(result);
connections++;
//serversync.BeginAccept(new AsyncCallback(OnConnectedSync), null);
try
{
txtStatus.Text = "" + connections;
byte[] message = Encoding.ASCII.GetBytes("Connected to Middleware");
sync.BeginSend(message, 0, message.Length, SocketFlags.None, new AsyncCallback(OnDataSentSync), sync);
}
catch
{
sync.Close();
}
}
void OnDataSent(IAsyncResult result)
{
Socket client = (Socket)result.AsyncState;
try
{
//end send and begin receive from client
int sent = client.EndSend(result);
client.BeginReceive(data, 0, data.Length, SocketFlags.None, new AsyncCallback(OnDataReceived), client);
}
catch (SocketException)
{
//close client
client.Close();
}
}
void OnDataSentSync(IAsyncResult result)
{
Socket sync = (Socket)result.AsyncState;
try
{
//end send and begin receive from client
int sent = sync.EndSend(result);
sync.BeginReceive(data, 0, data.Length, SocketFlags.None, new AsyncCallback(OnDataReceivedSync), sync);
}
catch (SocketException)
{
//close client
sync.Close();
}
}
void OnDataReceivedSync(IAsyncResult result)
{
Socket sync = (Socket)result.AsyncState;
//clientreturn = (Socket)result.AsyncState;
}
void OnDataSentWaiting(IAsyncResult result)
{
Socket sync = (Socket)result.AsyncState;
try
{
//end send and begin receive from client
int sent = sync.EndSend(result);
//sync.BeginReceive(data, 0, data.Length, SocketFlags.None, new AsyncCallback(OnDataReceived), sync);
}
catch (SocketException)
{
//close client
sync.Close();
}
}
void OnDataReceived(IAsyncResult result)
{
Socket client = (Socket)result.AsyncState;
clientreturn = (Socket)result.AsyncState;
try
{
//if nothing is received then close connection
//otherwise get message and add to list box
//create newsocket, bind and listen to create server connection
//begin accept
int receive;
receive = client.EndReceive(result);
//string port = (((IPEndPoint)client.RemoteEndPoint).Port.ToString ());
if (receive == 0)
{
client.Close();
return;
}
else
{
string message = Encoding.ASCII.GetString(data, 0, receive);
lstAll.Items.Add(message);
txtSent.Text = message;
byte[] echomessage = Encoding.ASCII.GetBytes(message);
bool check = remoteclient.Poll(1000, SelectMode.SelectRead);
bool avail = (remoteclient.Available == 0);
if (check & avail)
{
btnConnect.Enabled = true;
btnDisconnect.Enabled = false;
MessageWait(message);
//serversync.BeginSend(echomessage, 0, echomessage.Length, SocketFlags.None, new AsyncCallback(OnDataSentWaiting), serversync);
//client.BeginReceive(data, 0, data.Length, SocketFlags.None, new AsyncCallback(OnDataReceived), client);
}
else
{
client.BeginReceive(data, 0, data.Length, SocketFlags.None, new AsyncCallback(OnDataReceived), client);
remoteclient.BeginSend(echomessage, 0, echomessage.Length, SocketFlags.None, new AsyncCallback(OnRemoteDataSent), remoteclient);
}
}
}
catch (SocketException)
{
//close client
client.Close();
}
}
private void MessageWait(string message)
{
byte[] echomessage = Encoding.ASCII.GetBytes(message);
serversync.BeginSend(echomessage, 0, echomessage.Length, SocketFlags.None, new AsyncCallback(OnDataSentSync), null);
}
void OnRemoteDataSent(IAsyncResult result)
{
try
{
int sent = remoteclient.EndSend(result);
remoteclient.BeginReceive(data, 0, data.Length, SocketFlags.None, new AsyncCallback(OnRemoteDataReceived), null);
}
catch (SocketException)
{
//close server connection
remoteclient.Close();
}
}
void OnRemoteDataReceived(IAsyncResult result)
{
try
{
int receive = remoteclient.EndReceive(result);
string message = Encoding.ASCII.GetString(data, 0, receive);
txtReceived.Text = message + " from Middle";
datars = Encoding.ASCII.GetBytes(txtReceived.Text);
clientreturn.BeginSend(datars, 0, datars.Length, SocketFlags.None, new AsyncCallback(OnDataSentBack), clientreturn);
}
catch (SocketException)
{
//close server
clientreturn.Close();
}
}
void OnDataSentBack(IAsyncResult result)
{
Socket client = (Socket)result.AsyncState;
try
{
int sent = client.EndSend(result);
}
catch (SocketException)
{
//closeserver
client.Close();
}
}
private void btnConnect_Click(object sender, EventArgs e)
{
try
{
btnConnect.Enabled = false;
remoteclient = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint remoteEndPoint = new IPEndPoint(IPAddress.Parse(txtIP.Text), 2000);
remoteclient.BeginConnect(remoteEndPoint, new AsyncCallback(OnConnectedRemote), null);
}
catch
{
remoteclient.Close();
}
}
private void btnStart_Click(object sender, EventArgs e)
{
int port;
port = int.Parse(txtPort.Text);
btnStart.Enabled = false;
server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint localEP = new IPEndPoint(0, port);
server.Bind(localEP);
server.Listen(4);
server.BeginAccept(new AsyncCallback(OnConnected), null);
txtStatus.Text = "Waiting for client...";
}
private void btnSyncC_Click(object sender, EventArgs e)
{
int port;
port = int.Parse(txtPort.Text);
btnStart.Enabled = false;
serversync = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint localEP2 = new IPEndPoint(0, port);
serversync.Bind(localEP2);
serversync.Listen(1);
serversync.BeginAccept(new AsyncCallback(OnConnectedSync), null);
txtStatus.Text = "Waiting for sync client...";
}
}
}
答案 0 :(得分：0)
我敢打赌，txtStatus对象有问题，你实际上得到了一个NullReferenceException，它被捕获，被忽略，并导致套接字立即关闭。