.NET Error Closing serial port BaseStream error is only available when the port is open RRS feed

  • Question

  • I'm using the .NET System.IO.Ports.SerialPort using the BaseStream as suggested in this post If you must use .NET System.IO.Ports.SerialPort

    But when I try to close the port or the baseStream, an System.InvalidOperationException is raised saying "The BaseStream is only available when the port is open"

    This is my code:

          private void ActionStarted()
                //ajusta el puerto
                serial.Open();  //conecta al plc
                byte[] buffer = new byte[15];
                Action kickoffRead = null;
                if (serial.IsOpen) //si esta abierto el puerto hace todo esto
                    kickoffRead = delegate()
                        serial.BaseStream.BeginRead(buffer, 0, buffer.Length,
                            delegate(IAsyncResult ar)
                                    int actualLength = serial.BaseStream.EndRead(ar);
                                    byte[] received = new byte[actualLength];
                                    Buffer.BlockCopy(buffer, 0, received, 0, actualLength);
                            }, null);

    and the error occurrs when I try to close the window / port / basestream here, 

       private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)

    I read somewhere that the serial port should be close on a different thread but I can't find that, so any thoughts??


    Friday, January 16, 2015 5:21 PM


  • Hello franco,

    With your current provided code, it is hard to state something more specific about this exception. If it is possible, please provide a small demo sample code which could reproduce this issue.

    >> I read somewhere that the serial port should be close on a different thread but I can't find that, so any thoughts??

    From my experience, I would try to close the stream as soon as I obtain the data stored in the stream. Do you have a try to close stream as soon as after obtaining data from it to see if the stream could be closed successfully rather than closing it in the Window_Closing event? I  suggest that you could have a try.

    Since we cannot exactly reproduce this issue, here is a blog which might help you debug this issue deeply, you could debug into the .NET source code:



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    • Marked as answer by Fred Bao Tuesday, January 27, 2015 7:56 AM
    Monday, January 19, 2015 3:17 AM