Question

I have a windows form application in C#.Where i have a RichTextBox(Txt) in the Main window(MainForm) and a public method

public void postTxt(String txt)
{
    //do some database update
    this.Txt.AppendText(txt);
}

I have another Form called SerialTranseiver(MainForm mn) which is passed the MainForm as a parameter in the constructor.

SerialTranseiver(MainForm mn)
{
    //-----other codes
    this.tmpMain=mn;
}

This second class has a SerialPort(Sport) and waits for data and whenever data found in its
SerialDataReceivedEventHandler calls mn.postTxt(Sport.ReadLine().toString())

void Sport_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    mn.postTxt(Sport.ReadLine().toString());
    //---database updating codes and other stuff
 }

this causes an exception that says

Cross-thread operation not valid: Control 'Txt' accessed from a thread other than the thread it was created on

How can i solve this problem?

Answer 1

One way is to invoke a delegate asyncronously which is made public in the form you invoke it on. For example:

 mainForm.BeginInvoke(mainForm.logDelegate,destination,fileName,bytesSent, true);

I’d suggest you reading this first and this afterwards