Socket单客户端/服务器连接，服务器可以发送多次，客户端只能一次 [英] Socket single client/server connection, server can send multiple times, client can only once
本文介绍了Socket单客户端/服务器连接，服务器可以发送多次，客户端只能一次的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我写了一个客户端和服务器应用程序，我需要使用它来连接我在C＃中做的跳棋游戏。我有客户端和服务器连接，服务器可以重复发送客户端消息以更新标签，但是当客户端尝试发送消息时，它会抛出错误
I have written a client and server application that I need to use to connect a checkers game I made in C#. I have got the client and server to connect and the server can repeatedly send the client messages to update a label but when the client tries to send a message it throws the error
不允许发送或接收数据的请求，因为套接字未连接并且（当使用sendto调用在数据报套接字上发送时）没有提供地址。
"A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied."
以下是我的客户端和服务器。
Here is my client and server so far.
CLIENT -
CLIENT -
public partial class Form1 : Form //main form that establishes connection
{
Form2 form2 = new Form2();
Socket sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
Socket acc = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint endPoint;
static byte[] Buffer { get; set; }
string text;
public Form1()
{
InitializeComponent();
}
private void button1_Click_1(object sender, EventArgs e)
{
Thread rec = new Thread(recMsg);
Thread t = new Thread(ThreadProc);
t.Start(); //starts a form that will call the sendMsg on a button click
endPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 8887);
try
{
sck.Connect(endPoint);
}
catch
{
Console.WriteLine("unable to connect");
}
rec.Start();
text = textBox1.Text;
sendMsg(text);
}
public void sendMsg(string s)
{
//bool x = true;
//while (true)
//{
//Thread.Sleep(500);
//if (x == true)
//{
byte[] msgBuffer = Encoding.ASCII.GetBytes(s);
sck.Send(msgBuffer); //error comes here when i try to send a message from form2 says it isn't connected and has no address
// x = false;
//}
//} the commented out part doesn't effect how the send works it sends once and can't again, I think the problem is that the thread which establishes the connection dies but don't know how to solve.
}
public void recMsg()
{
while (true)
{
Thread.Sleep(500);
byte[] Buffer = new byte[255];
int rec = sck.Receive(Buffer, 0, Buffer.Length, 0);
Array.Resize(ref Buffer, rec);
form2.SetText(Encoding.Default.GetString(Buffer));
}
}
private void button2_Click(object sender, EventArgs e)
{
sck.Close();
}
public void ThreadProc()
{
form2.ShowDialog();
}
}
表单2有一个label1，textbox1和button1，将接受输入并调用Form1的主要操作形式sendMsg（）
Form 2 that has a label1, textbox1 and button1, main operating form that will take input and call the Form1 sendMsg()
public partial class Form2 : Form
{
delegate void SetTextCallback(string text);
Form1 form1;
public Form2()
{
InitializeComponent();
}
public void SetText(string text)
{
if (InvokeRequired)
{
SetTextCallback d = new SetTextCallback(SetText);
Invoke(d, new object[] { text });
}
else
{
label1.Text = text;
}
}
private void button1_Click(object sender, EventArgs e)
{
form1 = new Form1();
form1.sendMsg(textBox1.Text);
}
}
SERVER -
SERVER-
class Program
{
static Form1 form1 = new Form1();
static Form2 form2 = new Form2();
static byte[] buffer { get; set; }
static Socket sck, acc;
static string name;
static void Main(string[] args)
{
if (name == null)
{
Thread t = new Thread(ThreadProc);
t.Start();
}
Thread rec = new Thread(recMsg);
sck = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
sck.Bind(new IPEndPoint(0, 8887));
Console.WriteLine("Your local IP address is: " + getIP());
Console.WriteLine("Awaiting Connection");
sck.Listen(0);
acc = sck.Accept();
Console.WriteLine(" >> Accept connection from client");
rec.Start();
sendMsg();
}
static string getIP()
{
string hostName = System.Net.Dns.GetHostName();
IPHostEntry ipEntry = System.Net.Dns.GetHostEntry(hostName);
IPAddress[] addr = ipEntry.AddressList;
return addr[addr.Length - 1].ToString();
}
static void recMsg()
{
while (acc.Connected)
{
Thread.Sleep(500);
byte[] Buffer = new byte[255];
int rec = acc.Receive(Buffer, 0, Buffer.Length, 0);
Array.Resize(ref Buffer, rec);
form2.SetText(Encoding.Default.GetString(Buffer));
}
}
public void btnClick(string s)
{
name = s;
Console.WriteLine("Name: " + name);
System.Threading.Thread r = new System.Threading.Thread(new System.Threading.ThreadStart(ThreadProc2));
r.Start();
}
public void sendMSG(string s)
{
try
{
buffer = Encoding.Default.GetBytes(s);
acc.Send(buffer);
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
static void sendMsg()
{
try
{
buffer = Encoding.Default.GetBytes(name);
acc.Send(buffer);
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
public static void ThreadProc()
{
form1.ShowDialog();
}
public static void ThreadProc2()
{
form2.ShowDialog();
}
}
Form1 - 初始化表单，
Form1 - starter form that asks for a name, this form could be scrathed just used to build upon my basic server which will eventually be needed for the checkers game.
public partial class Form1 : Form
{
Program program;
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
this.Hide();
program = new Program();
program.btnClick(textBox1.Text);
}
}
Form2用作类似Form2的接口基本上有一个标签，文本框和按钮调用sendMsg（）
Form2 used as an interface like Form2 of my client that basically has a label, textbox and button that calls the sendMsg()
public partial class Form2 : Form
{
delegate void SetTextCallback(string text);
Program program = new Program();
public Form2()
{
InitializeComponent();
}
public void SetText(string text)
{
if (InvokeRequired)
{
SetTextCallback d = new SetTextCallback(SetText);
this.Invoke(d, new object[] { text });
}
else
{
this.label2.Text = text;
}
}
private void button1_Click(object sender, EventArgs e)
{
program.sendMSG(textBox1.Text);
}
}
重新介绍一下，此程序将连接，多次向客户端发送数据并更新标签。
To recap, this program will connect and the server can send data multiple times to the client and update a label. The client will send data to the server the first time and then it throws the error.
推荐答案
为什么不使用异步套接字呢？下面是一些代码：
Why not use asynchronous sockets? Here is some code:
// Server socket
class ControllerSocket : Socket, IDisposable
{
// MessageQueue queues messages to be processed by the controller
public Queue<MessageBase> messageQueue = null;
// This is a list of all attached clients
public List<Socket> clients = new List<Socket>();
#region Events
// Event definitions handled in the controller
public delegate void SocketConnectedHandler(Socket socket);
public event SocketConnectedHandler SocketConnected;
public delegate void DataRecievedHandler(Socket socket, int bytesRead);
public event DataRecievedHandler DataRecieved;
public delegate void DataSentHandler(Socket socket, int length);
public event DataSentHandler DataSent;
public delegate void SocketDisconnectedHandler();
public event SocketDisconnectedHandler SocketDisconnected;
#endregion
#region Constructor
public ControllerSocket(int port)
: base(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
{
// Create the message queue
this.messageQueue = new Queue<MessageBase>();
// Acquire the host address and port, then bind the server socket
IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());
IPAddress ipAddress = ipHostInfo.AddressList[0];
IPEndPoint localEndPoint = new IPEndPoint(ipAddress, port);
this.Bind(localEndPoint);
}
#endregion
// Starts accepting client connections
public void StartListening()
{
this.Listen(100);
this.BeginAccept(AcceptCallback, this);
}
// Connects to a client
private void AcceptCallback(IAsyncResult ar)
{
Socket listener = (Socket)ar.AsyncState;
Socket socket = listener.EndAccept(ar);
try
{
// Add the connected client to the list
clients.Add(socket);
// Notify any event handlers
if (SocketConnected != null)
SocketConnected(socket);
// Create an initial state object to hold buffer and socket details
StateObject state = new StateObject();
state.workSocket = socket;
state.BufferSize = 8192;
// Begin asynchronous read
socket.BeginReceive(state.Buffer, 0, state.BufferSize, 0,
ReadCallback, state);
}
catch (SocketException)
{
HandleClientDisconnect(socket);
}
finally
{
// Listen for more client connections
StartListening();
}
}
// Read data from the client
private void ReadCallback(IAsyncResult ar)
{
StateObject state = (StateObject)ar.AsyncState;
Socket socket = state.workSocket;
try
{
if (socket.Connected)
{
// Read the socket
int bytesRead = socket.EndReceive(ar);
// Deserialize objects
foreach (MessageBase msg in MessageBase.Receive(socket, bytesRead, state))
{
// Add objects to the message queue
lock (this.messageQueue)
messageQueue.Enqueue(msg);
}
// Notify any event handlers
if (DataRecieved != null)
DataRecieved(socket, bytesRead);
// Asynchronously read more client data
socket.BeginReceive(state.Buffer, state.readOffset, state.BufferSize - state.readOffset, 0,
ReadCallback, state);
}
else
{
HandleClientDisconnect(socket);
}
}
catch (SocketException)
{
HandleClientDisconnect(socket);
}
}
// Send data to a specific client
public void Send(Socket socket, MessageBase msg)
{
try
{
// Serialize the message
byte[] bytes = msg.Serialize();
if (socket.Connected)
{
// Send the message
socket.BeginSend(bytes, 0, bytes.Length, 0, SendCallback, socket);
}
else
{
HandleClientDisconnect(socket);
}
}
catch (SocketException)
{
HandleClientDisconnect(socket);
}
}
// Broadcast data to all clients
public void Broadcast(MessageBase msg)
{
try
{
// Serialize the message
byte[] bytes = msg.Serialize();
// Process all clients
foreach (Socket client in clients)
{
try
{
// Send the message
if (client.Connected)
{
client.BeginSend(bytes, 0, bytes.Length, 0, SendCallback, client);
}
else
{
HandleClientDisconnect(client);
}
}
catch (SocketException)
{
HandleClientDisconnect(client);
}
}
}
catch (Exception e)
{
// Serialization error
Console.WriteLine(e.ToString());
}
}
// Data sent to a client socket
private void SendCallback(IAsyncResult ar)
{
try
{
Socket socket = (Socket)ar.AsyncState;
if (socket.Connected)
{
// Complete sending the data
int bytesSent = socket.EndSend(ar);
// Notify any attached handlers
if (DataSent != null)
DataSent(socket, bytesSent);
}
else
{
HandleClientDisconnect(socket);
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
private void HandleClientDisconnect(Socket client)
{
// Client socket may have shutdown unexpectedly
if (client.Connected)
client.Shutdown(SocketShutdown.Both);
// Close the socket and remove it from the list
client.Close();
clients.Remove(client);
// Notify any event handlers
if (SocketDisconnected != null)
SocketDisconnected();
}
// Close all client connections
public void Dispose()
{
foreach (Socket client in clients)
{
if (client.Connected)
client.Shutdown(SocketShutdown.Receive);
client.Close();
}
}
}
// Client socket
class ReceiverSocket : Socket
{
// MessageQueue queues messages to be processed by the controller
public Queue<MessageBase> messageQueue = null;
#region Events
// Event definitions handled in the controller
public delegate void SocketConnectedHandler(Socket socket);
public event SocketConnectedHandler SocketConnected;
public delegate void DataRecievedHandler(Socket socket, MessageBase msg);
public event DataRecievedHandler DataRecieved;
public delegate void DataSentHandler(Socket socket, int length);
public event DataSentHandler DataSent;
public delegate void SocketDisconnectedHandler();
public event SocketDisconnectedHandler SocketDisconnected;
private IPEndPoint remoteEP = null;
#endregion
#region Constructor
public ReceiverSocket(int port)
: base(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
{
// Create the message queue
messageQueue = new Queue<MessageBase>();
// Acquire the host address and port
IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());
IPAddress ipAddress = ipHostInfo.AddressList[0];
remoteEP = new IPEndPoint(ipAddress, port);
}
#endregion
// Connect to the server
public void Connect()
{
this.BeginConnect(remoteEP, ConnectCallback, this);
}
// Server connected
private void ConnectCallback(IAsyncResult ar)
{
// Console.WriteLine("Connect Callback");
try
{
Socket client = (Socket)ar.AsyncState;
if (client.Connected)
{
client.EndConnect(ar);
// Console.WriteLine("Connect Callback - Connected");
// Create an initial state object to hold buffer and socket details
StateObject state = new StateObject();
state.workSocket = client;
state.BufferSize = 8192;
// Notify any event handlers
if (SocketConnected != null)
SocketConnected(client);
// Begin asynchronous read
client.BeginReceive(state.Buffer, state.readOffset, state.BufferSize - state.readOffset, 0,
ReceiveCallback, state);
}
else
{
// Console.WriteLine("Connect Callback - Reconnect");
Thread.Sleep(5000);
Connect();
}
}
catch (Exception ex)
{
// Attempt server reconnect
Reconnect();
}
}
// Read data from the server
private void ReceiveCallback(IAsyncResult ar)
{
try
{
StateObject state = (StateObject)ar.AsyncState;
Socket client = state.workSocket;
// Read the socket
if (client.Connected)
{
int bytesRead = client.EndReceive(ar);
// Deserialize objects
foreach (MessageBase msg in MessageBase.Receive(client, bytesRead, state))
{
// Add objects to the message queue
lock (this.messageQueue)
this.messageQueue.Enqueue(msg);
}
// Notify any event handlers
if (DataRecieved != null)
DataRecieved(client, null);
// Asynchronously read more server data
client.BeginReceive(state.Buffer, state.readOffset, state.BufferSize - state.readOffset, 0,
ReceiveCallback, state);
}
else
{
Reconnect();
}
}
catch (SocketException)
{
// Attempt server reconnect
Reconnect();
}
}
public void Send(MessageBase msg)
{
try
{
// Serialize the message
byte[] bytes = msg.Serialize();
if (this.Connected)
{
// Send the message
this.BeginSend(bytes, 0, bytes.Length, 0, SendCallback, this);
}
else
{
Reconnect();
}
}
catch (SocketException sox)
{
// Attempt server reconnect
Reconnect();
}
catch (Exception ex)
{
int i = 0;
}
}
private void SendCallback(IAsyncResult ar)
{
try
{
Socket client = (Socket)ar.AsyncState;
if (client.Connected)
{
// Complete sending the data
int bytesSent = client.EndSend(ar);
// Notify any event handlers
if (DataSent != null)
DataSent(client, bytesSent);
}
else
{
Reconnect();
}
}
catch (SocketException)
{
Reconnect();
}
}
// Attempt to reconnect to the server
private void Reconnect()
{
try
{
// Disconnect the original socket
if (this.Connected)
this.Disconnect(true);
this.Close();
// Notify any event handlers
if (SocketDisconnected != null)
SocketDisconnected();
}
catch (Exception e)
{
// Console.WriteLine(e.ToString());
}
}
}
// Encapsulates information about the socket and data buffer
public class StateObject
{
public Socket workSocket = null;
public int readOffset = 0;
public StringBuilder sb = new StringBuilder();
private int bufferSize = 0;
public int BufferSize
{
set
{
this.bufferSize = value;
buffer = new byte[this.bufferSize];
}
get { return this.bufferSize; }
}
private byte[] buffer = null;
public byte[] Buffer
{
get { return this.buffer; }
}
}
您需要做的只是插入自己
All you need to do is plug in your own messages.
请记住，套接字流可能（并且大多数时候）包含部分消息。因此，最好将消息的长度作为消息的第一个字节发送。您还必须通过在读取之间组合部分消息来相应地管理读取缓冲区。查看以下消息基类。
Keep in mind that the socket stream may (and most of the time do) contain partial messages. Therefore it is good practice to send the length of the message as the first bytes of a message. You also have to manage the read buffer accordingly by assembling partial messages between reads. Check out the following message base class.
public partial class MessageBase
{
// Virtual Execute method following the Command pattern
public virtual string Execute(Socket socket) { return string.Empty; }
protected virtual bool MustEncrypt
{
get { return false; }
}
// Binary serialization
public byte[] Serialize()
{
using (MemoryStream stream = new MemoryStream())
{
using (DeflateStream ds = new DeflateStream(stream, CompressionMode.Compress, true))
{
BinaryFormatter formatter = new BinaryFormatter();
formatter.Serialize(ds, this);
ds.Flush();
}
byte[] bytes = stream.GetBuffer();
byte[] bytes2 = new byte[stream.Length];
Buffer.BlockCopy(bytes, 0, bytes2, 0, (int)stream.Length);
// Array.Copy(bytes, bytes2, stream.Length);
if (this.MustEncrypt)
bytes2 = RijndaelEncrptor.Instance.Encrypt(bytes2);
// Create a buffer large enough to hold the encrypted message and size bytes
byte[] data = new byte[8 + bytes2.Length];
// Add the message size
BitConverter.GetBytes(bytes2.Length).CopyTo(data, 0);
BitConverter.GetBytes(this.MustEncrypt).CopyTo(data, 4);
// Add the message data
bytes2.CopyTo(data, 8);
return data;
}
}
static public MessageBase Deserialize(byte[] buffer)
{
int length = BitConverter.ToInt32(buffer, 0);
bool mustDecrypt = BitConverter.ToBoolean(buffer, 4);
MessageBase b = null;
try
{
b = MessageBase.Deserialize(buffer, 8, length, mustDecrypt);
}
catch { }
return b;
}
static public MessageBase Deserialize(byte[] buffer, int offset, int length, bool mustDecrypt)
{
// Create a buffer and initialize it with data from
// the input buffer offset by the specified offset amount
// and length determined by the specified length
byte[] data = new byte[length];
Buffer.BlockCopy(buffer, offset, data, 0, length);
// Array.Copy(buffer, offset, data, 0, length);
// Decrypt message
if (mustDecrypt)
data = RijndaelEncrptor.Instance.Decrypt(data);
// Deserialize the binary data into a new object of type MessageBase
using (MemoryStream stream = new MemoryStream(data))
{
using (DeflateStream ds = new DeflateStream(stream, CompressionMode.Decompress, false))
{
BinaryFormatter formatter = new BinaryFormatter();
try
{
return formatter.Deserialize(ds) as MessageBase;
}
catch
{
return null;
}
}
}
}
static public IEnumerable<MessageBase> Receive(Socket client, int bytesReceived, StateObject state)
{
// Total buffered count is the bytes received this read
// plus any unprocessed bytes from the last receive
int bufferLen = bytesReceived + state.readOffset;
// Reset the next read offset in the case
// this recieve lands on a message boundary
state.readOffset = 0;
// Make sure there are bytes to read
if (bufferLen >= 0)
{
// Initialize the current read position
int readOffset = 0;
// Process the receive buffer
while (readOffset < bufferLen)
{
// Get the message size
int length = BitConverter.ToInt32(state.Buffer, readOffset);
bool mustDecrypt = BitConverter.ToBoolean(state.Buffer, readOffset + 4);
// Increment the current read position by the length header
readOffset += 8;
// Change the buffer size if necessary
if (length + readOffset > state.Buffer.Length)
{
byte[] oldBuffer = new byte[state.BufferSize];
Buffer.BlockCopy(state.Buffer, 0, oldBuffer, 0, state.BufferSize);
// Array.Copy(state.Buffer, oldBuffer, state.BufferSize);
state.BufferSize = length + readOffset;
Buffer.BlockCopy(oldBuffer, 0, state.Buffer, 0, oldBuffer.Length);
// Array.Copy(oldBuffer, state.Buffer, oldBuffer.Length);
}
// Ensure there are enough bytes to process the message
if (readOffset + length <= bufferLen)
yield return MessageBase.Deserialize(state.Buffer, readOffset, length, mustDecrypt);
else
{
// Add back the message length
readOffset -= 8;
// Reorder the receive buffer so unprocessed
// bytes are moved to the start of the array
Buffer.BlockCopy(state.Buffer, 0, state.Buffer, 0, bufferLen - readOffset);
// Array.Copy(state.Buffer, state.Buffer, bufferLen - readOffset);
// Set the receive position to the current read position
// This is the offset where the next socket read will start
state.readOffset = bufferLen - readOffset;
break;
}
// Update the read position by the message length
readOffset += length;
}
}
}
}
The above code should get you going.
The above code should get you going.
这篇关于Socket单客户端/服务器连接，服务器可以发送多次，客户端只能一次的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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