高分请教。有关C#中的sokcet编程问题
最近刚学C#，遇到有关socket的问题，有请高手帮帮忙。
目的是想实现一个client/server最简单的通信，采用socket编程。
问题主要出现在客户端代码，服务器断能够接收到客户端的数据，但是客户端的receive总是没有反应。
如果把 if (connSocket.Available == 0) 这个判断去掉而直接receive的话，客户端程序会死掉。
不知道问题在那儿，100分有请高手解答！分数不是问题！不够再加！电脑旁等候回复信息。
//server端主要代码如下：
//省略了部分无关紧要的代码。
namespace myServer
{
public partial class frmMain : Form
{
private BackgroundWorker bwListener;
private Socket listenerSocket;
private IPAddress serverIP;
private int serverPort;
delegate void SetTextCallback(string text);
private Socket socket;
public frmMain()
{
InitializeComponent();
bwListener = new BackgroundWorker();
bwListener.WorkerSupportsCancellation = true;
bwListener.DoWork += new DoWorkEventHandler(StartToListen);
bwListener.RunWorkerAsync();
txtServerIP.Text = "192.168.1.10";
serverIP = IPAddress.Parse(txtServerIP.Text);
serverPort = 8000;
}
private void StartToListen(object sender, DoWorkEventArgs e)
{
string sendToClient = "OK! You can exit now!!!";
Byte[] bytesSentToClient = Encoding.ASCII.GetBytes(sendToClient);
Byte[] bytesReceived = new Byte[256];
this.listenerSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
this.listenerSocket.Bind(new IPEndPoint(this.serverIP, this.serverPort));
this.listenerSocket.Listen(200);
int bytes = 0;
string page = "Client's information: ";
while (true)
{
try
{
socket = this.listenerSocket.Accept();
SetText(((IPEndPoint)socket.RemoteEndPoint).Address.ToString());
do
{
bytes = socket.Receive(bytesReceived, bytesReceived.Length, 0);
int sendCount = 0;
socket.SendTimeout = 1000;
//在这里向客户端发送一句话，能够发送成功
sendCount = socket.Send(bytesSentToClient);
if (sendCount > 0)
MessageBox.Show("send success");
page = page + Encoding.ASCII.GetString(bytesReceived, 0, bytes);
}
while (bytes > 0);
}
catch (SocketException se)
{
MessageBox.Show(se.Message + "\r\n错误代码： " + se.ErrorCode);
return;
}
catch (Exception ee)
{
MessageBox.Show(ee.Message + "\r\n");
return;
}
DisconnectServer();
}
}
public void DisconnectServer()
{
this.bwListener.CancelAsync();
this.bwListener.Dispose();
this.listenerSocket.Close();
GC.Collect();
}
}
}
//-----------------------------------------
//客户端主要代码如下：
namespace test
{
public partial class ClientForm : Form
{
private Socket connSocket;
delegate void SetTextCallback(string text);
public ClientForm()
{
InitializeComponent();
}
private void btnConServer_Click(object sender, EventArgs e)
{
string host = "192.168.1.10";
int port = 8000;
host = txtServerIP.Text;
string result = SocketSendReceive(host, port);
}
private static Socket ConnectSocket(string server, int port)
{
Socket s = null;
IPHostEntry hostEntry = null;
// Get host related information.
hostEntry = Dns.GetHostEntry(server);
foreach (IPAddress address in hostEntry.AddressList)
{
IPEndPoint ipe = new IPEndPoint(address, port);
Socket tempSocket =
new Socket(ipe.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
try
{
tempSocket.Connect(ipe);
}
catch (SocketException e)
{
MessageBox.Show(e.Message + "\r\n错误代码： " + e.ErrorCode);
return null;
}
if (tempSocket.Connected)
{
s = tempSocket;
break;
}
else
{
continue;
}
}
return s;
}
// This method requests the home page content for the specified server.
private string SocketSendReceive(string server, int port)
{
string request = "connecting host: " + server +
"\r\n";
Byte[] bytesSent = Encoding.ASCII.GetBytes(request);
Byte[] bytesReceived = new Byte[1024];
// Create a socket connection with the specified server and port.
connSocket = ConnectSocket(server, port);
if (connSocket == null)
return ("Connection failed");
// Send request to the server.
connSocket.Send(bytesSent, bytesSent.Length, 0);
// Receive the server home page content.
int bytes = 0;
string page = "receiving data from host " + server + " \r\n";
// The following will block until te page is transmitted.
do
{
try
{
connSocket.ReceiveTimeout = 1000;
if (connSocket.Available == 0)
{
MessageBox.Show("没有数据可接收");
//return null;
}
/**********问题出现在这里*******/
//Receive总是不能成功！
bytes = connSocket.Receive(bytesReceived, bytesReceived.Length, 0);
if (bytes > 0)
MessageBox.Show("接收成功");
page = page + Encoding.ASCII.GetString(bytesReceived, 0, bytes);
}
catch (SocketException se)
{
MessageBox.Show(se.Message + "\r\n错误代码： " + se.ErrorCode);
return null;
}
catch
{
MessageBox.Show("错误代码!");
return null;
}
}
while (bytes > 0);
return page;
}
}
}
[解决办法]
太长 参考下些代码:
IPHostEntry ipHost = Dns.Resolve(地址);
TcpClient tcpClient = new TcpClient(ipHost.HostName , 端口);
NetworkStream Stream= tcpClient.GetStream(); //主动连接
然后可以
StreamReader stReader = new StreamReader(Stream); //读取流
用stReader监听数据
[解决办法]
接收放到另外一个线程中
Thread t=new Thread(new ThreadStart(aa));
t.start();
public void aa()
{
//接收程序
}
[解决办法]
接收数据为异步接收.
可以EMAIL一个完整的C#版本的服务与客户端程序给你.C++的就不能给.:)功能强大.呵
[解决办法]
这个方法是可行的。
using System;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Text;
// State object for receiving data from remote device.
public class StateObject {
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 256;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder();
}
public class AsynchronousClient {
// The port number for the remote device.
private const int port = 11000;
// ManualResetEvent instances signal completion.
private static ManualResetEvent connectDone =
new ManualResetEvent(false);
private static ManualResetEvent sendDone =
new ManualResetEvent(false);
private static ManualResetEvent receiveDone =
new ManualResetEvent(false);
// The response from the remote device.
private static String response = String.Empty;
private static void StartClient() {
// Connect to a remote device.
try {
// Establish the remote endpoint for the socket.
// The name of the
// remote device is "host.contoso.com".
IPHostEntry ipHostInfo = Dns.Resolve("host.contoso.com");
IPAddress ipAddress = ipHostInfo.AddressList[0];
IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);
// Create a TCP/IP socket.
Socket client = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp);
// Connect to the remote endpoint.
client.BeginConnect( remoteEP,
new AsyncCallback(ConnectCallback), client);
connectDone.WaitOne();
// Send test data to the remote device.
Send(client,"This is a test<EOF>");
sendDone.WaitOne();
// Receive the response from the remote device.
Receive(client);
receiveDone.WaitOne();
// Write the response to the console.
Console.WriteLine("Response received : {0}", response);
// Release the socket.
client.Shutdown(SocketShutdown.Both);
client.Close();
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
}
private static void ConnectCallback(IAsyncResult ar) {
try {
// Retrieve the socket from the state object.
Socket client = (Socket) ar.AsyncState;
// Complete the connection.
client.EndConnect(ar);
Console.WriteLine("Socket connected to {0}",
client.RemoteEndPoint.ToString());
// Signal that the connection has been made.
connectDone.Set();
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
}
private static void Receive(Socket client) {
try {
// Create the state object.
StateObject state = new StateObject();
state.workSocket = client;
// Begin receiving the data from the remote device.
client.BeginReceive( state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReceiveCallback), state);
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
}
private static void ReceiveCallback( IAsyncResult ar ) {
try {
// Retrieve the state object and the client socket
// from the asynchronous state object.
StateObject state = (StateObject) ar.AsyncState;
Socket client = state.workSocket;
// Read data from the remote device.
int bytesRead = client.EndReceive(ar);
if (bytesRead > 0) {
// There might be more data, so store the data received so far.
state.sb.Append(Encoding.ASCII.GetString(state.buffer,0,bytesRead));
// Get the rest of the data.
client.BeginReceive(state.buffer,0,StateObject.BufferSize,0,
new AsyncCallback(ReceiveCallback), state);
} else {
// All the data has arrived; put it in response.
if (state.sb.Length > 1) {
response = state.sb.ToString();
}
// Signal that all bytes have been received.
receiveDone.Set();
}
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
}
private static void Send(Socket client, String data) {
// Convert the string data to byte data using ASCII encoding.
byte[] byteData = Encoding.ASCII.GetBytes(data);
// Begin sending the data to the remote device.
client.BeginSend(byteData, 0, byteData.Length, 0,
new AsyncCallback(SendCallback), client);
}
private static void SendCallback(IAsyncResult ar) {
try {
// Retrieve the socket from the state object.
Socket client = (Socket) ar.AsyncState;
// Complete sending the data to the remote device.
int bytesSent = client.EndSend(ar);
Console.WriteLine("Sent {0} bytes to server.", bytesSent);
// Signal that all bytes have been sent.
sendDone.Set();
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
}
public static int Main(String[] args) {
StartClient();
return 0;
}
}
