The basic programming points and steps of the socket have been posted, and the code about the asynchronous socket communication is continued here.
Service (asynchronous):
Using system.net;
Using system.net.sockets;
Using system.io;
Using system.text;
Using system.threading;
Public Static ManualReveTevent Alldone = New ManualReveTevent (false);
Private thread th;
PRIVATE BOOL Listenerrun = True;
Socket Listener;
Private const Int max_socket = 10;
Protected Override Void Dispose (Bool Disposing)
{
Try
{
Listenerrun = false;
Th.abort ();
TH = NULL;
Listener.close ();
}
Catch {}
}
// Get the native IP address
// Get the native IP address
Public static ipaddress getServerip ()
{
IPHOSTENTRY IEH = DNS.GETHOSTBYNAME (DNS.GETHOSTNAME ());
Return IEh.AddressList [0];
}
// Listening method
Private void listen ()
{
Try
{
Int nport = int.parse (this.txtLocalport.Text);
Ipaddress serverip = get Serverip ();
IpendPoint IEP = New IpendPoint (ServerIP, NPORT);
Listener = New Socket (AddressFamily.internetwork, sockettype.stream, protocoltype.tcp);
Listener.bind (IEP);
Listener.listen (10);
Statusbar1.panels [0] .text = "port:" this.txtLocalport.text "is listening ...";
While (Listenerrun)
{
Alldone.reset ();
Listener.BeginAccept (new asyncCallback, listener);
Alldone.waitone ();
}
}
Catch (System.Security.securityException)
{
MessageBox.show ("Firewall Security Error!", "Error", MessageBoxButtons.ok, MessageBoxicon.exclamation;
}
}
// Asynchronous callback function
Public Void AcceptCallback (IASYNCRESULT AR)
{
Socket Listener = (socket) ar.asyncstate;
Socket Client = Listener.ndAccept (ar);
alldone.set ();
StateObject State = new stateObject ();
State.worksocket = client;
// remote information
Endpoint tempRemoteep = Client.RemoteEndPoint;
IpendPoint Tempremoteip = (ipendPoint) TempRemoteep; string remote = tempREMOTEIP.Address.tostring ();
String remoport = TempRemoteip.port.toString ();
IPHOSTENTRY HOST = DNS.GETOSTBYADDRESS (TempRemoteip.address);
String hostname = host.hostname;
Statusbar1.panels [1] .text = "Accept [" Hostname "]" RemPip ":" Remoport "Remote Computer is correctly connected!";
THISTBOXREMOHOST.ITEMS.ADD ("[" Hostname "]" Rempip ":" Remoport);
Client.BeginReceive (state.buffer, 0, stateObject.buffearsize, 0,
New asyncCallback (READCALLBACK), STATE);
}
// Asynchronously receive the backup function
Public Void ReadCallback (IasyncResult Ar)
{
StateObject State = (stateObject) ar.asyncState;
Socket Handler = State.Worksocket;
INT BYTESREAD = Handler.Endreceive (ar);
IF (BytesRead> 0)
{
String strmsg = encoding.ascii.getstring (state.buffer, 0, bytesread);
State.sb.append (strmsg);
String content = state.sb.tostring ();
// remote information
Endpoint tempRemoteep = handler.remoteEndpoint;
IpendPoint TempRemoteip = (ipendPoint) TempRemoteep;
String remoteip = tempRemoteip.address.tostring ();
String remoport = TempRemoteip.port.toString ();
IPHOSTENTRY HOST = DNS.GETOSTBYADDRESS (TempRemoteip.address);
String hostname = host.hostname;
Statusbar1.Panels [1] .text = "Information is receiving [" Hostname "]" Rempip ":" Remoport "...";
String time = datetime.now.tostring ();
ListBoxRecv.Items.add ("(" Time ")" Hostname ":");
ListBoxRecv.Items.Add (strmsg);
IF (Content.indexof ("/ x99 / x99")> -1)
{
Statusbar1.Panels [1] .text = "Information is completed!"; //
// Receive complete information
// MessageBox.show ("Receive:" Content);
String msg = powerd.codeparse (content);
Send (Handler, MSG); // Send
// send (content); // Send with separate Socket
}
Else
{
Handler.BeginReceive (state.buffer, 0, stateObject.buffearsize, 0,
New asyncCallback (READCALLBACK), STATE);
}
}
}
// Send
Private Void Send (Socket Handler, String Data)
{
Byte [] Bytedata = Encoding.ASCII.GetBytes (data);
Handler.beginsend (Bytedata, 0, Bytedata.length, 0,
New asyncCallback (SendCallback), Handler;
// Handler.send (ByTedata);
}
#Region // Send with separate Socket
Private Void Send (String Data)
{
// String ip = this.txtremoip.text;
// String port = this.txtremoport.text;
// ipaddress serverip = ipaddress.parse (IP);
// int serverport = convert.toint32 (port);
// IpendPoint IEP = New IpendPoint (ServerIP, Serverport);
// socket socket = new socket (addressfamily.internetwork, sockettype.stream, protocoltype.tcp);
// Socket.connect (IEP);
// Byte [] BYTEMESSAGE = Encoding.ascii.getbytes (DATA);
// socket.send (byteMessage);
// socket.shutdown (socketshutdown.both);
// socket.close ();
}
#ndregion
// Send a callback function asynchronous
// Send a callback function asynchronous
Private Static Void SendCallback (IasyncResult Ar)
{
Try
{
Socket Handler = (socket) ar.asyncState;
INT bytessent = handler.endsend (ar);
Messagebox.show ("Send Success!");
Handler.shutdown (socketshutdown.both);
Handler.close ();
}
Catch (Exception EX)
{
Messagebox.show (ex.totring ());
}
}
Private void btnlisten_click (object sender, system.eventargs e) {
TH = New Thread (New ThreadStart (Listen)); // Initialize the thread in the Listen process
Th.Start (); // Start this thread
this.btnlisten.enabled = false;
}
Private void btnclosenet_click (Object Sender, System.EventArgs E)
{
Try
{
Listenerrun = false;
Th.abort ();
TH = NULL;
Listener.close ();
Statusbar1.panels [0] .text = "is disconnected from the client!";
Statusbar1.Panels [1] .text = "";
}
Catch
{
Messagebox.show ("Connection has not been established, disconnected!", "Warning");
}
}
Private void btnexit_click (Object Sender, System.Eventargs E)
{
Try
{
Listenerrun = false;
Th.abort ();
TH = NULL;
Listener.close ();
Statusbar1.panels [0] .text = "is disconnected from the client!";
Statusbar1.Panels [1] .text = "";
}
Catch (Exception EX)
{
Messagebox.show (ex.Message);
}
Finally
{
Application.exit ();
}
}
// Status object to asynchronously
Public Class StateObject
{
Public Socket Worksocket = NULL;
Public const Int buffersize = 1024;
Public Byte [] buffer = new byte [buffersize];
Public StringBuilder SB = new stringbuilder ();
}
Client (synchronously send and receive):
Using system.net;
Using system.net.sockets;
Using system.io;
Using system.text;
Using system.threading;
Socket socket;
Int numByte = 1024; // number of bytes received at a time
Private void btnconnect_click (Object Sender, System.Eventargs E)
{
Try
{
String ip = this.txtremoip.text;
String port = this.txtremoport.text;
Ipaddress serverip = ipaddress.parse (IP);
INT ServerPort = Convert.Toint32 (Port);
IpendPoint IEP = New IpendPoint (ServerIP, Serverport);
IPHOSTENTRY HOST = DNS.GETOSTBYADDRESS (IEP.ADDRESS);
String hostname = host.hostname;
Socket = new socket (addressfamily.internetwork, sockettype.stream, protocoltype.tcp); socket.connect (IEP);
IpendPoint TempRemoteip = (ipendPoint) socket.localendpoint;
Statusbar1.Panels [0] .text = "port:" TempRemoteip.port.toString () "Listening ...";
Statusbar1.Panels [1] .text = "with remote computer [" Hostname "]" IP ":" port "to establish a connection!";
}
Catch
{
Statusbar1.panels [0] .Text = "Unable to connect to the target computer!";
}
#REGION
// ByteMessage = Encoding.ascii.getbytes (TextBox1.text "99");
// socket.send (byteMessage);
// Byte [] bytes = new byte [1024];
// Socket.Receive (bytes);
// String str = encoding.default.getstring (bytes);
// MessageBox.show ("Receive:" Str);
// socket.shutdown (socketshutdown.both);
// socket.close ();
#ndregion
}
Private void btnsend_click (Object Sender, System.Eventargs E)
{
Try
{
STATUSBAR1.PANELS [1] .text = "is sending information!";
String message = this.txtsend.text;
Sendinfo (MESSAGE);
}
CatCH // abnormal processing
{
Statusbar1.panels [0] .text = "Unable to send information to the target computer!"
}
}
Private void sendinfo (String Message)
{
#REGION
// String ip = this.txtip.text;
// String port = this.txtport.text;
//
// ipaddress serverip = ipaddress.parse (IP);
// int serverport = convert.toint32 (port);
// IpendPoint IEP = New IpendPoint (ServerIP, Serverport);
// Byte [] bytementage;
//
// Socket = New socket (addressfamily.internetwork, sockettype.stream, protocoltype.tcp);
// Socket.connect (IEP); # endregion
Byte [] bytemessage = encoding.ascii.getbytes (Message "/ x99 / x99);
Socket.send (ByteMessage);
// remote information
Endpoint tempRemoteep = Socket.RemoteEndPoint;
IpendPoint TempRemoteip = (ipendPoint) TempRemoteep;
String remoteip = tempRemoteip.address.tostring ();
String remoport = TempRemoteip.port.toString ();
IPHOSTENTRY HOST = DNS.GETOSTBYADDRESS (TempRemoteip.address);
String hostname = host.hostname;
//send Message
String Time1 = DateTime.now.toString ();
ListBoxSend.Items.Add ("( Time1 ") " Hostname ": ");
ListBoxSend.Items.Add (Message);
// is sent, directly receive
Stringbuilder SB = New StringBuilder ();
While (True)
{
Statusbar1.Panels [1] .text = "Waiting for receiving information ...";
Byte [] bytes = new byte [Numbyte];
INT recbytes = socket.receive (bytes);
String strmsg = encoding.default.getstring (bytes);
String time2 = datetime.now.toString ();
ListBoxRecv.Items.Add ("(" Time2 ")" Hostname ":");
ListBoxRecv.Items.Add (strmsg);
sb.append (strmsg);
IF (sb.tostring (). Indexof ("/ x99 / x99)> - 1)
{
Break;
}
}
Statusbar1.Panels [1] .text = "Receive information is completed!"
//
// code decoding
Codeparse (sb.toString ());
//
Socket.shutdown (socketshutdown.both);
Socket.close ();
}
