Question

I am working on a project for a physics class and would like to try and get an app together to perform the following. The test unit has a serial port on it that is outputting data at 1 Hz. I would like to have an app that will read the serial port data and save it to a file. I have created this in a Console app and it works fine. Now, I would like a GUI. On the main screen of the GUI I would like a couple of check boxes. One where the user can add a timestamp to the incoming data stream, one to output the data to a text file, and may be one to send the data to my graphite graphing server.

So, I am looking for some pointers here. Right now, I have a connect button. When pressed, it opens the serial port and performs a serial.readline() But if no data is currently being pushed across the link, the app is locked up. So I am assuming I need to use threading. Does this sound correct?

And last, how do I handle the check boxes? I would like 4 total buttons. Connect/Disconnect Record/Pause. At least these is my thoughts.

Answer 1

Instead of creating a thread for the serial port just hook into the DataReceived event.

As for the checkboxes hook into the CheckedChanged event.

So it would look something like:

private bool paused;
private SerialPort sp;

public Form1()
{
    InitializeComponent();

    sp = new SerialPort();
    sp.DataReceived += new SerialDataReceivedEventHandler(sp_DataReceived);
}

private void sp_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    if (!paused)
    {
        string indata = sp.ReadExisting();

        //Display the data
        //To avoid cross thread problems do something like this
        Invoke(new Action(() =>
        {
            textBox1.Text += indata;
        }));

        //Or if you are just writing to the console 
        Console.WriteLine(indata); //Thread safe

        //Timestamp checkbox
        if (checkBox3.Checked)
        {
            //Display timestamp using DateTime.Now  
        }

    //Write to file checkbox
    if (checkBox4.Checked)
    {
        using (StreamWriter file = new StreamWriter(path, true))
        {
            file.WriteLine(indata);
        } 
    }
}
}

//Pause/Resume Checkbox
private void checkBox1_CheckedChanged(object sender, EventArgs e)
{
    paused = checkBox1.Checked;
}

//Connect/Disconnect checkbox
private void checkBox2_CheckedChanged(object sender, EventArgs e)
{
    if (checkBox2.Checked)
    {
        sp.Open();
    }
    else
    {
        sp.Close();
    }
}