/// <summary>
/// Connect to the telnet server
/// </summary>
/// <returns>true if connection was successful</returns>
public bool Connect()
{
// check for buffer
if (this.buffer == null)
this.buffer = new byte[RECEIVEBUFFERSIZE];
// virtual screen
if (this.virtualScreen == null)
this.virtualScreen = new VirtualScreen(this.vsWidth, this.vsHeight, 1, 1);
// set the callbacks
if (this.callBackReceive == null)
this.callBackReceive = new AsyncCallback(ReadFromStream);
if (this.callBackSend == null)
this.callBackSend = new AsyncCallback(WriteToStream);
// flags
this.serverEcho = false;
this.clientInitNaws = false;
this.firstResponse = true;
this.nawsNegotiated = false;
this.forceLogout = false;
// return physical connection
if (this.tcpClient != null)
return true; // we still have a connection -> ?? better reconnect ??
else {
try {
// TODO: Improve performance ...?
// This is not working: IPAddress ipAddress = IPAddress.Parse(this.hostName);
// IPEndPoint ipEndPoint = new IPEndPoint(ipAddress, this.port);
// because it addresses local endpoints
this.tcpClient = new TcpClient(this.hostName, this.port);
this.tcpClient.ReceiveTimeout = this.timeoutReceive;
this.tcpClient.SendTimeout = this.timeoutSend;
this.tcpClient.NoDelay = true;
this.tcpClient.GetStream().BeginRead(this.buffer, 0, this.buffer.Length, this.callBackReceive, null);
return true;
} catch {
this.tcpClient = null;
return false;
}
}
}
/// <summary>
/// Closes external resources.
/// Safe, can be called multiple times
/// </summary>
public void Close()
{
// physical connection
if (this.tcpClient != null) {
try {
if (this.tcpClient.GetStream() != null) {
// it is important to close the stream
// because somehow tcpClient does not physically breaks down
// the connection - on "one connection" telnet server the
// server remains blocked if not doing it!
try {
this.tcpClient.GetStream().Close();
} catch {
// further handling would go here
}
}
this.tcpClient.Close();
this.tcpClient = null;
} catch {
this.tcpClient = null;
}
}
this.virtualScreen = null;
this.buffer = null;
this.callBackReceive = null;
this.callBackSend = null;
this.forceLogout = false;
}