C chat program server and client complete instance code
- 2020-06-23 01:48:05
- OfStack
This article describes the C# based implementation of the multi-user chat program server and client complete code. This example omitted the structure definition part, the server side mainly is the logic processing part of the code, therefore needs to perfect 1 form button and so on when using.
Take a look at the server code as follows:
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Net;
using System.Net.Sockets;
using System.Threading;
namespace Multiplayer chat program Server end
{
/// <summary>
/// The main entry point to the application.
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
// Start service button
private void button2_Click(object sender, System.EventArgs e)
{
try
{
// Port must be filled in
if(txtPort.Text == "")
{
MessageBox.Show(" Please fill in the service port number first !", " prompt ");
return;
}
Int32 port = Int32.Parse(txtPort.Text); // Get the port number
// Create listening Socket
mainSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint localEP = new IPEndPoint(IPAddress.Any, port);
// will Socket Bind to a local endpoint
mainSocket.Bind(localEP);
// Start listening. The maximum number of connections is 5
mainSocket.Listen(5);
// start 1 An asynchronous operation accepts a client's connection request
mainSocket.BeginAccept(new AsyncCallback(OnClientConnect), null);
// The start service button is not available and the stop service button is available
UpdateControls(true);
}
catch(SocketException se)
{
MessageBox.Show(se.Message, " prompt ");
}
}
// Update the status of the Start Service button and Stop Service button: is it available?
// Note: The states of the two buttons are mutually exclusive
private void UpdateControls(bool onServe)
{
button2.Enabled = !onServe;
button3.Enabled = onServe;
if(onServe)
{
status.Text = " Started service ";
}
else
{
status.Text = " Unstarted service ";
}
}
// The callback function will be called when the client connects
public void OnClientConnect(IAsyncResult asyn)
{
try
{
// call EndAccept complete BeginAccept Asynchronous call, return 1 A new one Socket Handle communication with customers
Socket workerSocket = mainSocket.EndAccept(asyn);
// Increase the number of customers
Interlocked.Increment(ref clientNum);
// will workerSocket Socket To join the ArrayList In the
workerSocketList.Add(workerSocket);
// Send a welcome message to the customer who is connected to the server
string msg = " Welcome customer " + clientNum + " Login server \n";
SendWelcomeToClient(msg, clientNum);
// The number of online customers has changed and the customer list must be updated
UpdateClientListControl();
// The customer on the connection receives the data
WaitForData(workerSocket, clientNum);
// The main Socket Return and continue to wait for other connection requests
mainSocket.BeginAccept(new AsyncCallback(OnClientConnect), null);
}
catch(ObjectDisposedException)
{
System.Diagnostics.Debugger.Log(0,"1","\n OnClientConnection: Socket Has been closed !\n");
}
catch(SocketException se)
{
MessageBox.Show(se.Message, " prompt ");
}
}
// Send a welcome message to the customer
void SendWelcomeToClient(string msg, int clientNumber)
{
// with UTF8 Format to string Transform information into byte An array
byte[] byData = System.Text.Encoding.UTF8.GetBytes(msg);
// Get the customer clientNumber The corresponding Socket
Socket workerSocket = (Socket)workerSocketList[clientNumber - 1];
// Send the data to the customer
workerSocket.Send(byData);
}
// This class saves the current socket , its customer number and the data sent to the server
public class SocketPacket
{
public System.Net.Sockets.Socket currentSocket; // The current Socket
public int clientNumber; // Customer number
public byte[] dataBuffer = new byte[1024]; // Data sent to the server
// The constructor
public SocketPacket(System.Net.Sockets.Socket socket, int clientNumber)
{
currentSocket = socket;
this.clientNumber = clientNumber;
}
}
// Start waiting for the customer to send data
public void WaitForData(System.Net.Sockets.Socket socket, int clientNumber)
{
try
{
if(pfnWorkerCallBack == null)
{
// The callback function is called when the client on the connection has a write operation
pfnWorkerCallBack = new AsyncCallback(OnDataReceived);
}
SocketPacket socketPacket = new SocketPacket(socket, clientNumber);
socket.BeginReceive(socketPacket.dataBuffer, 0, socketPacket.dataBuffer.Length,
SocketFlags.None, pfnWorkerCallBack, socketPacket);
}
catch(SocketException se)
{
MessageBox.Show (se.Message, " prompt ");
}
}
// When a customer writes data, the following method is called
public void OnDataReceived(IAsyncResult asyn)
{
SocketPacket socketData = (SocketPacket)asyn.AsyncState ;
try
{
// EndReceive complete BeginReceive An asynchronous call that returns the number of bytes the customer wrote into the stream
int iRx = socketData.currentSocket.EndReceive(asyn);
// add 1 Because the string starts with '\0' As the end flag
char[] chars = new char[iRx + 1];
// Conduct information from customers UTF8 Decode, store chars Character array
System.Text.Decoder decoder = System.Text.Encoding.UTF8.GetDecoder();
int charLen = decoder.GetChars(socketData.dataBuffer, 0, iRx, chars, 0);
System.String szData = new System.String(chars);
string msg = " The customer " + socketData.clientNumber + " Send the information :" + szData;
// Add the data sent by the customer to the information list
AppendToRichEditControl(msg);
// Waiting for data
WaitForData(socketData.currentSocket, socketData.clientNumber);
}
catch (ObjectDisposedException )
{
System.Diagnostics.Debugger.Log(0,"1","\nOnDataReceived: Socket Has been closed !\n");
}
catch(SocketException se)
{
if(se.ErrorCode == 10054)
{
// Writes the client disconnect information to the information list
string msg = " The customer " + socketData.clientNumber + " The connection has been disconnected !" + "\n";
AppendToRichEditControl(msg);
// Remove the closed ones socket
workerSocketList[socketData.clientNumber - 1] = null;
// Update customer list
UpdateClientListControl();
}
else
{
MessageBox.Show (se.Message, " prompt ");
}
}
}
// Update the list of information that can be called by the main thread or another worker thread
private void AppendToRichEditControl(string msg)
{
// Test to see which thread called the method
if (InvokeRequired)
{
// We cannot update the GUI on this thread.
// All GUI controls are to be updated by the main (GUI) thread.
// Hence we will use the invoke method on the control which will
// be called when the Main thread is free
// Do UI update on UI thread
object[] pList = {msg};
txtRecvMsg.BeginInvoke(new UpdateRichEditCallback(OnUpdateRichEdit), pList);
}
else
{
// Create the main thread of the control to update the list of information directly
OnUpdateRichEdit(msg);
}
}
// Add information to txtRecvMsg In the
private void OnUpdateRichEdit(string msg)
{
// txtRecvMsg.AppendText(msg);
txtRecvMsg.Text = txtRecvMsg.Text + msg;
}
// Update customer list
private void UpdateClientListControl()
{
if (InvokeRequired) // Is this called from a thread other than the one created
// the control
{
clientList.BeginInvoke(new UpdateClientListCallback(UpdateClientList), null);
}
else
{
// Create the main thread of the control to update the list of information directly
UpdateClientList();
}
}
// Update customer list
void UpdateClientList()
{
clientList.Items.Clear(); // Clear customer list
for(int i = 0; i < workerSocketList.Count; i++)
{
// add 1 That's because the array starts from the subscript 0 And our customer number is from 1 start
string clientKey = Convert.ToString(i + 1);
Socket workerSocket = (Socket)workerSocketList[i];
if(workerSocket != null)
{
// Add the customers connected to the server to the customer list
if(workerSocket.Connected)
{
clientList.Items.Add(clientKey);
}
}
}
}
// Stop button
private void button3_Click(object sender, System.EventArgs e)
{
CloseSockets();
UpdateControls(false);
// Update customer list
UpdateClientListControl();
}
// Send message button
private void button1_Click(object sender, System.EventArgs e)
{
// If the online customer list is not empty, messages are allowed to be sent
if (clientList.Items.Count != 0 )
{
try
{
string msg = txtSendMsg.Text;
msg = " Server information : " + msg + "\n";
byte[] byData = System.Text.Encoding.UTF8.GetBytes(msg);
Socket workerSocket = null;
for(int i = 0; i < workerSocketList.Count; i++)
{
workerSocket = (Socket)workerSocketList[i];
if(workerSocket!= null)
{
// To all customers connected to the server
if(workerSocket.Connected)
{
workerSocket.Send(byData);
}
}
}
}
catch(SocketException se)
{
MessageBox.Show(se.Message, " prompt ");
}
}
else
{
MessageBox.Show(" No online customers , Can't send a message !", " prompt ");
}
}
// Clear information button
private void button4_Click(object sender, System.EventArgs e)
{
txtRecvMsg.Clear(); // Empty messages from customers
}
// Close form button
private void button5_Click(object sender, System.EventArgs e)
{
CloseSockets();
Close();
}
// Shut down Socket
void CloseSockets()
{
// Shut down the main Socket
if(mainSocket != null)
{
mainSocket.Close();
}
Socket workerSocket = null;
// Shut down the customer Socket An array of
for(int i = 0; i < workerSocketList.Count; i++)
{
workerSocket = (Socket)workerSocketList[i];
if(workerSocket != null)
{
workerSocket.Close();
workerSocket = null;
}
}
}
private void Form1_Load(object sender, System.EventArgs e)
{
try
{
// Obtain the local IP address
txtIP.Text = Dns.Resolve(Dns.GetHostName()).AddressList[0].ToString();
// On startup, the Start service button is available and the Stop service button is not
UpdateControls(false);
}
catch(Exception exc)
{
MessageBox.Show(exc.Message, " prompt ");
}
}
}
}The client mainly realizes the operation interface of receiving messages returned from the server and sending messages, creates Socket instance, gets the IP address of the server, updates the control, connects and disconnects, etc. The specific code is as follows:
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Net;
using System.Net.Sockets;
namespace Multiplayer chat program Client end
{
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Label label1;
private System.Windows.Forms.TextBox txtIP;
private System.Windows.Forms.Label label2;
private System.Windows.Forms.Label label3;
private System.Windows.Forms.RichTextBox txtSendMsg;
private System.Windows.Forms.Label label4;
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.Windows.Forms.Button button3;
private System.Windows.Forms.Button button4;
private System.Windows.Forms.RichTextBox txtRecvMsg;
private System.Windows.Forms.TextBox txtPort;
private System.Windows.Forms.Button button5;
private System.ComponentModel.Container components = null;
byte[] m_dataBuffer = new byte[10];
IAsyncResult result;
public AsyncCallback pfnCallBack ;
private System.Windows.Forms.Label status;
private System.Windows.Forms.Label label5;
public Socket clientSocket;
public Form1()
{
InitializeComponent();
}
private void InitializeComponent()
{
this.label1 = new System.Windows.Forms.Label();
this.txtIP = new System.Windows.Forms.TextBox();
this.label2 = new System.Windows.Forms.Label();
this.txtPort = new System.Windows.Forms.TextBox();
this.label3 = new System.Windows.Forms.Label();
this.txtSendMsg = new System.Windows.Forms.RichTextBox();
this.label4 = new System.Windows.Forms.Label();
this.status = new System.Windows.Forms.Label();
this.txtRecvMsg = new System.Windows.Forms.RichTextBox();
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.button3 = new System.Windows.Forms.Button();
this.button4 = new System.Windows.Forms.Button();
this.label5 = new System.Windows.Forms.Label();
this.button5 = new System.Windows.Forms.Button();
this.SuspendLayout();
// label1
this.label1.AutoSize = true;
this.label1.Location = new System.Drawing.Point(16, 24);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(60, 17);
this.label1.TabIndex = 0;
this.label1.Text = " The server IP:";
// txtIP
this.txtIP.Location = new System.Drawing.Point(80, 24);
this.txtIP.Name = "txtIP";
this.txtIP.Size = new System.Drawing.Size(160, 21);
this.txtIP.TabIndex = 1;
this.txtIP.Text = "";
// label2
this.label2.AutoSize = true;
this.label2.Location = new System.Drawing.Point(16, 56);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(35, 17);
this.label2.TabIndex = 2;
this.label2.Text = " port :";
// txtPort
this.txtPort.Location = new System.Drawing.Point(80, 56);
this.txtPort.Name = "txtPort";
this.txtPort.Size = new System.Drawing.Size(40, 21);
this.txtPort.TabIndex = 3;
this.txtPort.Text = "";
// label3
this.label3.AutoSize = true;
this.label3.Location = new System.Drawing.Point(16, 96);
this.label3.Name = "label3";
this.label3.Size = new System.Drawing.Size(110, 17);
this.label3.TabIndex = 4;
this.label3.Text = " Send a message to the server :";
// txtSendMsg
this.txtSendMsg.Location = new System.Drawing.Point(16, 120);
this.txtSendMsg.Name = "txtSendMsg";
this.txtSendMsg.Size = new System.Drawing.Size(224, 88);
this.txtSendMsg.TabIndex = 5;
this.txtSendMsg.Text = "";
// label4
this.label4.AutoSize = true;
this.label4.Location = new System.Drawing.Point(16, 248);
this.label4.Name = "label4";
this.label4.Size = new System.Drawing.Size(60, 17);
this.label4.TabIndex = 6;
this.label4.Text = " Connection status :";
// status
this.status.Location = new System.Drawing.Point(80, 248);
this.status.Name = "status";
this.status.Size = new System.Drawing.Size(192, 23);
this.status.TabIndex = 7;
// txtRecvMsg
this.txtRecvMsg.Location = new System.Drawing.Point(264, 80);
this.txtRecvMsg.Name = "txtRecvMsg";
this.txtRecvMsg.ReadOnly = true;
this.txtRecvMsg.Size = new System.Drawing.Size(224, 144);
this.txtRecvMsg.TabIndex = 8;
this.txtRecvMsg.Text = "";
// button1
this.button1.Location = new System.Drawing.Point(280, 16);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(88, 32);
this.button1.TabIndex = 9;
this.button1.Text = " The connection ";
this.button1.Click += new System.EventHandler(this.button1_Click);
// button2
this.button2.Location = new System.Drawing.Point(384, 16);
this.button2.Name = "button2";
this.button2.Size = new System.Drawing.Size(88, 32);
this.button2.TabIndex = 10;
this.button2.Text = " Disconnect the ";
this.button2.Click += new System.EventHandler(this.button2_Click);
// button3
this.button3.Location = new System.Drawing.Point(280, 232);
this.button3.Name = "button3";
this.button3.Size = new System.Drawing.Size(88, 32);
this.button3.TabIndex = 11;
this.button3.Text = " Clear information ";
this.button3.Click += new System.EventHandler(this.button3_Click);
// button4
this.button4.Location = new System.Drawing.Point(384, 232);
this.button4.Name = "button4";
this.button4.Size = new System.Drawing.Size(88, 32);
this.button4.TabIndex = 12;
this.button4.Text = " Shut down ";
this.button4.Click += new System.EventHandler(this.button4_Click);
// label5
this.label5.AutoSize = true;
this.label5.Location = new System.Drawing.Point(264, 64);
this.label5.Name = "label5";
this.label5.Size = new System.Drawing.Size(134, 17);
this.label5.TabIndex = 13;
this.label5.Text = " Receive the message from the server :";
// button5
this.button5.Location = new System.Drawing.Point(16, 208);
this.button5.Name = "button5";
this.button5.Size = new System.Drawing.Size(224, 32);
this.button5.TabIndex = 14;
this.button5.Text = " Send a message ";
this.button5.Click += new System.EventHandler(this.button5_Click);
// Form1
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(512, 277);
this.Controls.Add(this.button5);
this.Controls.Add(this.label5);
this.Controls.Add(this.button4);
this.Controls.Add(this.button3);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Controls.Add(this.txtRecvMsg);
this.Controls.Add(this.status);
this.Controls.Add(this.label4);
this.Controls.Add(this.txtSendMsg);
this.Controls.Add(this.label3);
this.Controls.Add(this.txtPort);
this.Controls.Add(this.label2);
this.Controls.Add(this.txtIP);
this.Controls.Add(this.label1);
this.Name = "Form1";
this.Text = " Multiplayer chat program Client end ";
this.Load += new System.EventHandler(this.Form1_Load);
this.ResumeLayout(false);
}
#endregion
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
// Connect button
private void button1_Click(object sender, System.EventArgs e)
{
// IP The address and port number cannot be empty
if(txtIP.Text == "" || txtPort.Text == "")
{
MessageBox.Show(" Please fill in the server completely first IP Address and port number !", " prompt ");
return;
}
try
{
// create Socket The instance
clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
// Get the server's IP address
IPAddress ipAddress = IPAddress.Parse(txtIP.Text);
Int32 port = Int32.Parse(txtPort.Text);
// Create a remote endpoint
IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);
// Connect to a remote server
clientSocket.Connect(remoteEP);
if(clientSocket.Connected)
{
UpdateControls(true);
WaitForData(); // Asynchronous wait data
}
}
catch(SocketException se)
{
MessageBox.Show (se.Message, " prompt ");
UpdateControls(false);
}
}
// Waiting for data
public void WaitForData()
{
try
{
if(pfnCallBack == null)
{
// The callback function is called when the client on the connection has a write operation
pfnCallBack = new AsyncCallback(OnDataReceived);
}
SocketPacket socketPacket = new SocketPacket();
socketPacket.thisSocket = clientSocket;
result = clientSocket.BeginReceive(socketPacket.dataBuffer, 0, socketPacket.dataBuffer.Length,
SocketFlags.None, pfnCallBack, socketPacket);
}
catch(SocketException se)
{
MessageBox.Show(se.Message, " prompt ");
}
}
// This class to save Socket And the data sent to the server
public class SocketPacket
{
public System.Net.Sockets.Socket thisSocket;
public byte[] dataBuffer = new byte[1024]; // Data sent to the server
}
// Receive data
public void OnDataReceived(IAsyncResult asyn)
{
try
{
SocketPacket theSockId = (SocketPacket)asyn.AsyncState ;
// EndReceive complete BeginReceive An asynchronous call that returns the number of bytes the server wrote to the stream
int iRx = theSockId.thisSocket.EndReceive(asyn);
// add 1 Because the string starts with '\0' As the end flag
char[] chars = new char[iRx + 1];
// with UTF8 Format to string Transform information into byte An array
System.Text.Decoder decoder = System.Text.Encoding.UTF8.GetDecoder();
int charLen = decoder.GetChars(theSockId.dataBuffer, 0, iRx, chars, 0);
System.String szData = new System.String(chars);
// Displays the received information in the information list
txtRecvMsg.Text = txtRecvMsg.Text + szData;
// Waiting for data
WaitForData();
}
catch (ObjectDisposedException)
{
System.Diagnostics.Debugger.Log(0,"1","\nOnDataReceived: Socket Has been closed !\n");
}
catch(SocketException se)
{
if(se.ErrorCode == 10054)
{
string msg = " The server " + " Stop the service !" + "\n";
txtRecvMsg.Text = txtRecvMsg.Text + msg;
clientSocket.Close();
clientSocket = null;
UpdateControls(false);
}
else
{
MessageBox.Show(se.Message, " prompt ");
}
}
}
// Update the control. The states of the connect and disconnect (send messages) buttons are mutually exclusive
private void UpdateControls(bool connected)
{
button1.Enabled = !connected;
button2.Enabled = connected;
button5.Enabled = connected;
if(connected)
{
status.Text = " The connected ";
}
else
{
status.Text = " There is no connection ";
}
}
// Disconnect button
private void button2_Click(object sender, System.EventArgs e)
{
// Shut down Socket
if(clientSocket != null)
{
clientSocket.Close();
clientSocket = null;
UpdateControls(false);
}
}
// Send message button
private void button5_Click(object sender, System.EventArgs e)
{
try
{
// If the client is connected to the server, it is allowed to send the information
if(clientSocket.Connected)
{
string msg = txtSendMsg.Text + "\n";
// with UTF8 Format to string Transform information into byte An array
byte[] byData = System.Text.Encoding.UTF8.GetBytes(msg);
if(clientSocket != null)
{
// To send data
clientSocket.Send(byData);
}
}
}
catch(Exception se)
{
MessageBox.Show(se.Message, " prompt ");
}
}
// Delete button
private void button3_Click(object sender, System.EventArgs e)
{
txtRecvMsg.Clear(); // Clear the information list
}
// Close button
private void button4_Click(object sender, System.EventArgs e)
{
// Shut down Socket
if(clientSocket != null)
{
clientSocket.Close();
clientSocket = null;
}
Close(); // Closed form
}
private void Form1_Load(object sender, System.EventArgs e)
{
UpdateControls(false); // When initialized, only the connection button is available
}
}
}