DOTNET (C #) Basic socket programming)

Http://blog.csdn.net/itfly8/archive/2006/03/13/622877.aspx

Basic socket programming

Server:

Using system. net;

Using system. net. Sockets;

Using system. text;

Using system. Threading;

 

Thread mythread;

Socket socket;

// Clear all resources in use.

Protected override void dispose (bool disposing)

{

Try

{

Socket. Close (); // release resources

Mythread. Abort (); // abort a thread

}

Catch {}

 

If (disposing)

{

If (components! = NULL)

{

Components. Dispose ();

}

}

Base. Dispose (disposing );

}

Public static IPaddress getserverip ()

{

Iphostentry IEH = DNS. gethostbyname (DNS. gethostname ());

Return IEH. Addresslist [0];

}

Private void beginlisten ()

{

IPaddress serverip = getserverip ();

Ipendpoint IEP = new ipendpoint (serverip, 8000 );

Socket = new socket (addressfamily. InterNetwork, sockettype. Stream, protocoltype. TCP );

 

Byte [] bytemessage = new byte [1, 100];

This. label1.text = IEP. tostring ();

Socket. BIND (IEP );

// Do

While (true)

{

Try

{

Socket. Listen (5 );

Socket newsocket = socket. Accept ();

Newsocket. Receive (bytemessage );

 

String stime = datetime. Now. tow.timestring ();

String MSG = stime + ":" + "Message from :";

MSG + = newsocket. remoteendpoint. tostring () + encoding. Default. getstring (bytemessage );

This. listbox1.items. Add (MSG );

 

}

Catch (socketexception ex)

{

This. label1.text + = ex. tostring ();

}

}

// While (bytemessage! = NULL );

}

// Start listening

Private void button#click (Object sender, system. eventargs E)

{

Try

{

Mythread = new thread (New threadstart (beginlisten ));

Mythread. Start ();

 

}

Catch (system. Exception ER)

{

MessageBox. Show (ER. message, "finished", messageboxbuttons. OK, messageboxicon. Stop );

}

}

 

 

Client:

 

Using system. net;

Using system. net. Sockets;

Using system. text;

 

Private void button#click (Object sender, system. eventargs E)

{

Beginsend ();

}

Private void beginsend ()

{

String ipdomainthis.txt IP. text;

String portdeskthis.txt port. text;

 

IPaddress serverip = IPaddress. parse (IP );

Int SERVERPORT = convert. toint32 (port );

Ipendpoint IEP = new ipendpoint (serverip, SERVERPORT );

Byte [] bytemessage;

// Do

//{

Socket socket = new socket (addressfamily. InterNetwork, sockettype. Stream, protocoltype. TCP );

Socket. Connect (IEP );

 

Bytemessage = encoding. ASCII. getbytes (textbox1.text );

Socket. Send (bytemessage );

Socket. Shutdown (socketshutdown. Both );

Socket. Close ();

//}

// While (bytemessage! = NULL );

}

 

Transmission and receiving end based on TCP protocol

 

TCP Receiver

 

Using system. net. Sockets; // use the tcplisten class

Using system. Threading; // use the thread

Using system. IO; // use streamreader class

 

Int Port = 8000; // define the listening port number

Private thread ththreadread; // creates a thread to listen on the port number and receive information.

Private tcplistener tltcplisten; // listener port number

Private bool blistener = true; // sets the flag bit to determine the listening status

Private networkstream nsstream; // create the received basic data stream

Private streamreader srread;

Private system. Windows. Forms. statusbar statusbar1;

Private system. Windows. Forms. Button button1;

Private system. Windows. Forms. ListBox listbox1; // read data from the basic network data stream

Private tcpclient tcclient;

 

Private void listen ()

{

Try

{

Tltcplisten = new tcplistener (port); // initialize the tcplistener instance on the port 8000

Tltcplisten. Start (); // start listening

Statusbar1.text = "listening ...";

Tcclient = tltcplisten. accepttcpclient (); // TCP Connection Request

Nsstream = tcclient. getstream (); // obtain the basic network data stream used to send and receive data

Srread = new streamreader (nsstream); // obtains the basic network data stream to initialize the streamreader instance.

Statusbar1.text = "connected! ";

 

While (blistener) // loop listener

{

String smessage = srread. Readline (); // read a row of data from the basic network data stream

If (smessage = "stop") // determines whether the TCP Connection Control code is disconnected.

{

Tltcplisten. Stop (); // disable listening

Nsstream. Close (); // release resources

Srread. Close ();

Statusbar1.text = "the connection has been closed! ";

Ththreadread. Abort (); // abort a thread

Return;

}

 

String stime = datetime. Now. tow.timestring (); // the time when the data is received.

Listbox1.items. Add (stime + "" + smessage );

}

}

Catch (system. Security. securityexception)

{

MessageBox. Show ("failed to listen! "," Error ");

}

}

// Start listening

Private void button#click (Object sender, system. eventargs E)

{

Ththreadread = new thread (New threadstart (Listen ));

Ththreadread. Start (); // start the thread

Button1.enabled = false;

}

// Clear all resources in use.

Protected override void dispose (bool disposing)

{

Try

{

Tltcplisten. Stop (); // disable listening

Nsstream. Close ();

Srread. Close (); // release resources

Ththreadread. Abort (); // abort a thread

}

Catch {}

 

If (disposing)

{

If (components! = NULL)

{

Components. Dispose ();

}

}

Base. Dispose (disposing );

}

 

Sending end of TCP protocol

 

Using system. net. Sockets; // use the tcplisten class

Using system. Threading; // use the thread

Using system. IO; // use streamwriter class

Using system. Net; // use the IPaddress class and iphostentry class.

 

Private streamwriter swwriter; // used to transmit data to the basic network data stream

Private networkstream nsstream; // create the network-based data stream for data transmission

Private tcpclient;

Private system. Windows. Forms. Button button1;

Private system. Windows. Forms. textbox textbox1;

Private system. Windows. Forms. Button button2;

Private system. Windows. Forms. textbox textbox2;

Private system. Windows. Forms. statusbar statusbar1;

Private system. Windows. Forms. Label label1;

Private system. Windows. Forms. Label label2; // submit a TCP connection request to the remote host.

Private bool tcpconnect = false; // defines the identifier to indicate whether a TCP connection is established.

 

// Connection

Private void button#click (Object sender, system. eventargs E)

{

IPaddress ipremote;

Try

{

Ipremote = IPaddress. parse (textbox1.text );

}

Catch // determine the validity of a given IP Address

{

MessageBox. Show ("The Entered IP address is invalid! "," Error message! ");

Return;

}

 

Iphostentry iphost;

Try

{

Iphost = DNS. Resolve (textbox1.text );

}

Catch // determine whether the host corresponding to the IP address is online

{

MessageBox. Show ("the remote host is not online! "," Error message! ");

Return;

}

 

String shostname = iphost. hostname;

Try

{

Tcpclient = new tcpclient (shostname, 8000); // apply for a TCP connection to port 8000 of the remote host

Nsstream = tcpclient. getstream (); // obtain the basic network data stream for data transmission through application

Swwriter = new streamwriter (nsstream); // use the obtained basic network data stream to initialize the streamwriter instance.

Button1.enabled = false;

Button2.enabled = true;

Tcpconnect = true;

Statusbar1.text = "connected! ";

}

Catch

{

MessageBox. Show ("cannot establish a connection with the remote host port 8000! "," Error message! ");

Return;

}

}

 

// Send

Private void button2_click (Object sender, system. eventargs E)

{

If (textbox2.text! = "")

{

Swwriter. writeline (textbox2.text); // refresh the data in the current data stream

Swwriter. Flush ();

}

Else

{

MessageBox. Show ("The message cannot be blank! "," Error message! ");

}

}

// Clear all resources in use.

Protected override void dispose (bool disposing)

{

If (tcpconnect)

{

Swwriter. writeline ("stop"); // send control code

Swwriter. Flush (); // refresh the data in the current data stream

Nsstream. Close (); // clear Resources

Swwriter. Close ();

}

If (disposing)

{

If (components! = NULL)

{

Components. Dispose ();

}

}

Base. Dispose (disposing );

}