How to reach RichTextbox1 from a static method?

Question

vs2019 Windows Form app (not web) there is the Serial IO and its event handler that uses a delegate,
public static void DataReceivedHandler(object sender, SerialDateReceivedEventArgs e) {

serialport sp = (SerialPort)sender;
read, put into string, etc...

}

HOW to get that data into RichTextBox1 ? or if not possible how to even use that data? Since its static it wont see the form. anything Ive tried gets a RUNTIME error saying cross thread something or other. trying to modify RichTextBox1 from a thread that didnt create it. Sorry, you lose!

whats the solution? use of Assembly? Win32 calls making the handler from scratch?

Answer 1

Thanks, well that got it closer, found the answer to be:

  private delegate void AppendTextDelegate(string text, RichTextBox rtb);

        private void AppendText(string text, RichTextBox rtb)
        {
            if (rtb.InvokeRequired)
            {
                rtb.Invoke(new AppendTextDelegate(AppendText), text, rtb);
            }
            else
            {
                rtb.AppendText(text + Environment.NewLine);
            }
        }

Answer 2

If the "cross-thread" issue is the only problem, then replace the statements like richTextBox1.Text = "some text" with:

richTextBox1.Invoke( new Action( ( ) => richTextBox1.Text = "some text" ) );

Answer 3

richTextBox1.Invoke( new Action( ( ) => richTextBox1.Text = "some text" ) );

compiler says "Action"? not known unless I missed something else Action was not defined, not found