A tcp and UPD chat and file transfer program

A tcp and UPD chat and file transfer program

Author: Hebei ca Wang xuesong

Download source code

Abstract:

This article uses examples to show how to chat, send files to each other, and capture the screen of the recipient to save as a file in the LAN. The program also includes obtaining the IP address and computer name of the Local Machine and the other party. The first time I published an article on functions such as the rolling ListBox control, I just remembered the efficacy of throwing a brick and mortar. errors are inevitable. Please don't take it for me. Thank you.

The running interface is as follows:

1. Start and terminate the listening thread (only about TCP)

This program can be switched instantly, so it is necessary to end the thread that is still in the accept state.
// TCP listening thread

Uint _ listentcpthread (lpvoid lparam) {cmyqqdlg * pdlg = (cmyqqdlg *) lparam; csocket socksrvr; pdlg-> m_potr = port + pdlg-> m_server; // Save the current port, used to disable int createsucceed = socksrvr. create (pdlg-> m_potr); int listensucceed = socksrvr. listen (); // start listening to csocket recso; sockaddr_in client; int iaddrsize = sizeof (client); int acceptsucceed = socksrvr. accept (recso, (sockaddr *) & client, & iaddrsize); // accept the connection and obtain the peer ipsocksrvr. close (); char flag [F Lag] = {0}; // acceptance mark, used to identify received information, files, and other if (recso. Receive (flag, flag )! = 2) {return-1;} pdlg-> m_type = Flag [0]; If (pdlg-> m_type = ''d') return 0; // terminate this thread pthreadlisen =: afxbeginthread (_ listentcpthread, pdlg); pdlg-> receivefilemsg (recso, client); Return 0 ;}

Close

If (m_nsocktype = sock_tcp) {DWORD dwstatus; If (pthreadlisen! = NULL) {If (: getexitcodethread (pthreadlisen-> m_hthread, & dwstatus) = 0) {int errror = getlasterror (); return;} If (dwstatus = still_active) {csocket sockclient; sockclient. create (); cstring IP, strerror; IP = "127.0.0.1"; int conn = sockclient. connect (IP, m_potr); If (conn = 0) {afxmessagebox ("Close error! "+ Geterror (getlasterror (); sockclient. shutdown (2); sockclient. close (); return;} sockclient. send ("D", flag); // end }}

2. Send and accept files. Relatively simple. See the source program. Send

For (;) {num = myfile. read (m_buf, sizefile); If (num = 0) break; // After the file is read, end = sockclient. send (m_buf, num );}

Accept

For (;) {n = recso. receive (BUF, sizefile); // accept if (n = 0) break; // 0 indicates the end of F. write (BUF, n );}

3. For more information about chatting, see the source program.

Else if (m_type = 'm'') // information {char buff [100] = {0}; cstring MSG; int ret = 0; (;;) {ret = recso. receive (buff, 100); If (ret = 0) break; MSG + = Buff;} cstring Strout, strin; m_you_ip.getwindowtext (strin); getnamebyaddress (strin, Strout ); cstring youname; youname. format (inet_ntoa (client. sin_addr); cstring STR = youname + "<-" + Strout; addmsglist (STR, MSG );}

4. There are many examples in the VC knowledge base for screen capture. Tested on vc6 + Win2000.