How to send byte value using comport?

I am trying the example UART project at

All is good. The serial port only has a write method that takes string parameter, I’d like to send a byte (0-255) value. My question is, how do I convert values above 128 to string? Is there other method to send raw data (0-255) using serialport?

You find all member functions of the SerialPort class on MSDN. There is a function called Write that does the what you want.

public void Write(
	byte[] buffer,
	int offset,
	int count

The reference can be found here.

Thanks, exactly what I need.