Question

I am getting out of memory alert in this function, called 500K times:

public void DoStuff(string msg)
{
     rtfTerminal.Invoke(new EventHandler(delegate
            {
                rtfTerminal.SelectedText = string.Empty;
                rtfTerminal.AppendText(msg);
                rtfTerminal.ScrollToCaret();

            }));

}

In the global scope I declared:

  private System.Windows.Forms.RichTextBox rtfTerminal;

• I guess I get the out of memory since I do new EventHandler each
  call, How can I avoid that?
• Is it reasonable that I get the out of memory due to
  rtfTerminal.AppendText(msg);?

Answer 1

The new EventHandler is not a massive problem, nor is the anonymous object that you can’t really see (but which exists): both of these will be short-lived, i.e. GEN-0 and will virtually free to collect. Additionally, GC will kick in if things start to run low, so that shouldn’t be a problem. Continually adding text to a RichTextBox without limit could be a problem. I would try to avoid that. Files are usually a better option for dumping output from long-running processes.

Ultimately, if that doesn’t help: you need to use something like a memory profiler to see where the memory is going.