Serial port communication set the port mode programatically

That's pretty simple in .Net. You need to add these library:

using System.IO.Ports;

To open/close a port:

serialport.Open();
serialport.Close();

but you need to be carefull not the open an open one. You need to check if it's open or not with:

serialport.IsOpen();

Then you can use SerialPort class and make necassery adjustments like Port name, baudrate, parity, handshake...

seriPort.PortName = ....;
serialPort.BaudRate = ...;
serialPort.Parity = Parity.None;
serialPort.Handshake = Handshake.RequestToSend;

Also, you can get all the serialPort(including virtual ones) names using this little code:

serialport.GetPortNames();

Have Fun :)