Question

I’m writing code that reads from a COM port. I want it to read from two ports without having to close the first port and open the second one. How would I go about doing this?

Answer 1

using System.IO.Ports;

...

SerialPort port1 = new SerialPort("COM1", 9600, Parity.None, 8, StopBits.One);
SerialPort port2 = new SerialPort("COM2", 9600, Parity.None, 8, StopBits.One);

port1.DataReceived += new SerialDataReceivedEventHandler(port1_DataReceived);
port2.DataReceived += new SerialDataReceivedEventHandler(port2_DataReceived);
port1.Open();
port2.Open();

...

private void port1_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    // Show all the incoming data in the port's buffer
    Console.WriteLine(port1.ReadExisting());
}
private void port2_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    // Show all the incoming data in the port's buffer
    Console.WriteLine(port2.ReadExisting());
}