C # network programming (1) -- C # simple lan Communication

Requirements:

1. Server:

2. Client:

3. The client sends a message to the server. After receiving the message, the server displays the message and sends the confirmation message.

 

The server code is as follows:

Using system; <br/> using system. collections. generic; <br/> using system. LINQ; <br/> using system. text; <br/> using system. net; <br/> using system. net. sockets; </P> <p> namespace lan_server <br/> {<br/> public class server <br/>{< br/> Public static void main () <br/> {<br/> try <br/> {<br/> // instance that converts an IP address to IPaddress <br/> IPaddress iPad = IPaddress. parse ("127.0.0.1"); </P> <p> // initialize the listener. Port: 8001 <br/> tcplistener mylist = new tcplistener (IPAD, 8001 ); </P> <p> // start listening to the server port <br/> mylist. start (); </P> <p> // output server startup information <br/> console. writeline ("Start service on port 8001... "); <br/> console. writeline ("local node:" + mylist. localendpoint); <br/> console. writeline ("waiting for connection ..... "); </P> <p> // wait for the access connection request to be processed <br/> // the newly established connection is represented by socket S. <br/> socket S = mylist. acceptsocket (); <br/> console. writeline ("connection from" + S. remoteendpoint); </P> <p> // receives client information <br/> byte [] B = new byte [100]; <br/> int K = S. receive (B); <br/> console. writeline ("received... "); <br/> for (INT I = 0; I <K; I ++) <br/> {<br/> console. write (convert. tochar (B [I]); <br/>}</P> <p> // process client requests, respond to the client <br/> asciiencoding ASEN = new asciiencoding (); <br/> S. send (ASEN. getbytes ("the string was recieved by the server. "); <br/> console. writeline ("/n Response Message sent"); <br/> console. read (); </P> <p> // release resources in the aftermath <br/> S. close (); <br/> mylist. stop (); <br/>}< br/> catch (exception e) <br/>{< br/> console. writeline ("error ..... "+ E. stacktrace); <br/>}</P> <p>

The client code is as follows:

Using system; <br/> using system. collections. generic; <br/> using system. LINQ; <br/> using system. io; <br/> using system. net; <br/> using system. text; <br/> using system. net. sockets; </P> <p> namespace lan_client <br/> {<br/> public class client <br/>{< br/> Public static void main () <br/>{< br/> try <br/> {<br/> // create a client socket <br/> tcpclient tcpclnt = new tcpclient (); <br/> console. writeline ("connection ..... "); </P> <p> // connect to the server <br/> tcpclnt. connect ("maid", 8001); <br/> console. writeline ("connected"); <br/> console. write ("Enter the string to be transmitted:"); </P> <p> // read the string <br/> string STR = console. readline (); </P> <p> // obtain the stream of the client <br/> stream STM = tcpclnt. getstream (); </P> <p> // sending string <br/> asciiencoding ASEN = new asciiencoding (); <br/> byte [] BA = Asen. getbytes (STR); <br/> console. writeline ("transmission ..... "); <br/> STM. write (BA, 0, ba. length); </P> <p> // receives the information returned from the server <br/> byte [] BB = new byte [100]; <br/> int K = STM. read (BB, 0,100); </P> <p> // information returned by the output server <br/> for (INT I = 0; I <K; I ++) <br/> {<br/> console. write (convert. tochar (BB [I]); <br/>}< br/> console. read (); </P> <p> // close the client connection <br/> tcpclnt. close (); <br/>}< br/> catch (exception e) <br/>{< br/> console. writeline ("error ..... "+ E. stacktrace); <br/>}< br/>

The running result is as follows:

 

Defects:

(1) Real-time dialogs are not allowed.

(2) The connection cannot be closed manually.