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c#.netserial-port

C# check if a COM (Serial) port is already open


Is there an easy way of programmatically checking if a serial COM port is already open/being used?

Normally I would use:

try
{
    // open port
}
catch (Exception ex)
{
    // handle the exception
}

However, I would like to programatically check so I can attempt to use another COM port or some such.


Solution

  • I needed something similar some time ago, to search for a device.

    I obtained a list of available COM ports and then simply iterated over them, if it didn't throw an exception i tried to communicate with the device. A bit rough but working.

    var portNames = SerialPort.GetPortNames();
    
    foreach(var port in portNames) {
        //Try for every portName and break on the first working
    }