A simple chat program (Socket)

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Service-Side server code:

Using system;using system.collections.generic;using system.componentmodel;using system.data;using System.Drawing; Using system.io;using system.linq;using system.net;using system.net.sockets;using system.text;using System.Threading     Using system.threading.tasks;using system.windows.forms;namespace Socket Network programming _server{public partial class Form1:form        {public Form1 () {InitializeComponent (); } private void btnStart_Click (object sender, EventArgs e) {try {//when clicked When you start listening, create a socket socket Socketwatch = new socket (addressfamily.internetwork, sockettype) on the server side that is responsible for monitoring IP addresses and port numbers.                Stream, PROTOCOLTYPE.TCP);                IPAddress IP = ipaddress.any;                Create a port number object IPEndPoint point = new IPEndPoint (IP, Convert.ToInt32 (txtport.text));                Monitor Socketwatch.bind (point);                ShowMsg ("monitor success");               Socketwatch.listen (10); Thread th = new Thread (Listen); Th.                IsBackground = true; Th.            Start (Socketwatch);        } catch {}}///<summary>//wait for client connection and create socket for communication with        </summary> Socket Socketsend;            void Listen (Object o)//The function executed by the thread, if there is an argument, must be the Object type {socket socketwatch = O as socket; Wait for the client to connect and create a socket for communication while (true) {try {/                    /Socket socketsend = Socketwatch.accept () that is responsible for communicating with the client;                    The IP address and socket of the remote connected client are deposited into the collection Dicsocket.add (SocketSend.RemoteEndPoint.ToString (), socketsend);                    The IP address and socket of the remote connected client are deposited into the drop-down box CboUsers.Items.Add (socketSend.RemoteEndPoint.ToString ());                 192.168.11.87: Connection succeeded ShowMsg (socketSend.RemoteEndPoint.ToString () + ": Connection succeeded");   Open a new thread and receive the message from the client thread th = new Thread (Recive); Th.                    IsBackground = true; Th.                Start (Socketsend);        } Catch {}}}//Put the IP address and socket of the remote connected client into the collection        dictionary<string, socket> dicsocket = new dictionary<string, socket> (); <summary>//server-side receive messages from clients///</summary>//<param name= "O" &GT;&LT;/PARAM&G        T            void Recive (Object o) {socket socketsend = O as socket;                    while (true) {try {//Client connection succeeds, the server should accept the information sent by the client                    byte[] buffer = new BYTE[1024 * 1024 * 2];                    The actual number of valid bytes received int r = socketsend.receive (buffer);                    if (r = = 0) {break; } string str = Encoding.UTF8.GetString (buffer, 0, R);                ShowMsg (Socketsend.remoteendpoint + ":" + str); } Catch {}}} void ShowMsg (String str) {Txtlo        G.appendtext (str + "\ r \ n");  private void Form1_Load (object sender, EventArgs e) {control.checkforillegalcrossthreadcalls =        False }///<summary>//The server sends a message to the client///</summary>//<param name= "Sender" ><        /param>//<param name= "E" ></param> private void Btnsend_click (object sender, EventArgs e)                {try {string str = Txtmsg.text;                byte[] buffer = Encoding.UTF8.GetBytes (str);                list<byte> list = new list<byte> (); List.                ADD (0); List.                AddRange (buffer); Converts a generic collection to a collection byte[] Newbuffer = list. ToarrAy ();                Get the IP address of the user in the dropdown box always selected string IP = cboUsers.SelectedItem.ToString (); DICSOCKET[IP].                Send (Newbuffer);            Socketsend.send (buffer); } catch {}}///<summary>//Select the file to send/        </summary>//<param name= "sender" ></param>//<param name= "E" ></param> private void Btnselect_click (object sender, EventArgs e) {OpenFileDialog ofd = new OpenFileDialog            (); Ofd.            Title = "Please select"; Ofd.            InitialDirectory = @ "C:\Users\Administrator\Desktop"; Ofd.            Filter = "All Files |*.*"; Ofd.            ShowDialog (); Txtpath.text = ofd.        FileName; private void Btnsendfile_click (object sender, EventArgs e) {//Get the path of the file to be sent by string pat            h = txtpath.text; using (FileStream fsread=new FileStream (path,filemode.open,fileaccesS.read) {byte[] buffer = new BYTE[1024 * 1024 * 5]; int r = fsread.read (buffer, 0, buffer.                Length);                list<byte> list = new list<byte> (); List.                ADD (1); List.                AddRange (buffer); byte[] Newbuffer = list.                ToArray (); Dicsocket[cbousers.selecteditem.tostring ()].            Send (newbuffer, 0, r+1, socketflags.none); }}///<summary>//Send vibration///</summary>//<param name= "Sender" &GT;&L        t;/param>//<param name= "E" ></param> private void Btnzd_click (object sender, EventArgs e)            {byte[] buffer = new BYTE[1];            Buffer[0] = 2; Dicsocket[cbousers.selecteditem.tostring ()].        Send (buffer); }    }}

Client-side code:

Using system;using system.collections.generic;using system.componentmodel;using system.data;using System.Drawing; Using system.io;using system.linq;using system.net;using system.net.sockets;using system.text;using System.Threading     Using system.threading.tasks;using system.windows.forms;namespace Socket Network programming _client{public partial class Form1:form        {public Form1 () {InitializeComponent ();        } Socket Socketsend; private void btnStart_Click (object sender, EventArgs e) {try {//create Socke for communication T 1: Represents IP V4 2: What type of Stream, Stream 3: corresponding service socketsend = new Socket (AddressFamily.InterNetwork, Sockettype.st                Ream, PROTOCOLTYPE.TCP);                The IP address of the text box needs to be converted to the IPAddress type IPAddress IP = ipaddress.parse (txtserver.text);                The port number needs to be converted to the IPEndPoint type IPEndPoint point = new IPEndPoint (IP, Convert.ToInt32 (txtport.text)); Get the IP of the remote server application you want to connect toAddress and port number Socketsend.connect (point);                ShowMsg ("Connection succeeded");                A new thread is turned on to receive the message from the server side thread th = new Thread (Recive); Th.                IsBackground = true; Th.            Start (); } catch {}}///<summary>///non-stop receiving messages from the server///</summary> Voi D Recive () {while (true) {try {byte[] buf                    fer = new BYTE[1024 * 1024 * 3];                    The actual number of valid bytes received int r = socketsend.receive (buffer);                    if (r = = 0) {break;                        }//First to determine if the text message is sent if (buffer[0] = = 0) {                        Note that the decoding takes from the first start to the length-1 bytes of string s = Encoding.UTF8.GetString (buffer, 1, r-1); ShowMsg (Socketsend.remoteendpoint + ":" + s); } if (buffer[0] = = 1) {SaveFileDialog SFD = new savefiledial                        OG (); SfD.                        InitialDirectory = @ "C:\Users\Administrator\Desktop"; SfD.                        Title = "Please select the file to be saved"; SfD.                        Filter = "All Files |*.*"; SfD.                        ShowDialog (this);//Do not add this bounce? String path = sfd.                        FileName;                            using (FileStream fswrite=new FileStream (path,filemode.openorcreate,fileaccess.write)) {                        Fswrite.write (BUFFER,1,R-1);                    } MessageBox.Show ("Saved successfully");                    } if (buffer[0] = = 2) {ZD (); }} catch {}}}//<summary>//shake///<         /summary> void ZD () {   for (int i = 0; i <, i++) {this.                Location = new Point (200, 200); This.             Location = new Point (280,280);        }} void ShowMsg (String str) {Txtlog.appendtext (str + "\ r \ n"); }///<summary>//client sends a message to the server///</summary>//<param name= "Sender" ><        /param>//<param name= "E" ></param> private void Btnsend_click (object sender, EventArgs e)            {String str = TxtMsg.Text.Trim ();            byte[] buffer = Encoding.UTF8.GetBytes (str);        Socketsend.send (buffer);  private void Form1_Load (object sender, EventArgs e) {control.checkforillegalcrossthreadcalls =        False }    }}

A simple chat program (Socket)