C / C++ / MFC

IMyClass * DLL_API CreateMyClass();
DLL_API DestroyMyClass(IMyClass *);

pSocket.Connect((LPCTSTR(strAddress), iPort);
int nErrorCode = WSAGetLastError();
if (nErrorCode != 0)
	{
		switch( nErrorCode )
		{
         case WSAENETDOWN: 
            AfxMessageBox("The Windows Sockets implementation detected that the network subsystem failed.");
            break;
         case WSAEACCES: 
            AfxMessageBox("The requested address is a broadcast address, but the appropriate flag was not set.");
            break;
         case WSAEINPROGRESS: 
            AfxMessageBox("A blocking Windows Sockets operation is in progress.");
            break;
         case WSAEFAULT: 
            AfxMessageBox("The lpBuf argument is not in a valid part of the user address space.");
            break;
         case WSAENETRESET: 
            AfxMessageBox("The connection must be reset because the Windows Sockets implementation dropped it.");
            break;
         case WSAENOBUFS: 
            AfxMessageBox("The Windows Sockets implementation reports a buffer deadlock.");
            break;
         case WSAENOTCONN: 
            AfxMessageBox("The socket is not connected.");
            break;
         case WSAENOTSOCK: 
            AfxMessageBox("The descriptor is not a socket.");
            break;
         case WSAEOPNOTSUPP: 
            AfxMessageBox("MSG_OOB was specified, but the socket is not of type SOCK_STREAM.");
            break;
         case WSAESHUTDOWN: 
            AfxMessageBox("The socket has been shut down; it is not possible to call Send on a socket after ShutDown has been invoked with nHow set to 1 or 2.");
            break;
         case WSAEWOULDBLOCK: 
            AfxMessageBox("The socket is marked as nonblocking and the requested operation would block.");
            break;
         case WSAEMSGSIZE: 
            AfxMessageBox("The socket is of type SOCK_DGRAM, and the datagram is larger than the maximum supported by the Windows Sockets implementation.");
            break;
         case WSAEINVAL: 
            AfxMessageBox("The socket has not been bound with Bind.");
            break;
         case WSAECONNABORTED: 
            AfxMessageBox("The virtual circuit was aborted due to timeout or other failure.");
            break;
		 case WSAECONNRESET: 
            AfxMessageBox("The virtual circuit was reset by the remote side.");
            break;
         default:
            TCHAR szError[256];
            wsprintf(szError, "OnConnect error: %d", nErrorCode);
            AfxMessageBox(szError);
            break;
		}
	}