title: Load RTF into Winforms Richtextbox "in stages"
body: <p>I need to display a large (>8000 lines) RTF-formatted text in my <strong>Winforms RichTextBox</strong>. But while texts up to ~500 lines appear instantly in the RichTextBox, a large text like this <strong>takes a couple of minutes</strong>.</p>
  
  <p>So I was thinking, is there any way to load the Richtext <strong>in smaller portions</strong> into the RichTextBox, i.e. only when the user is scrolling further down?</p>
  
  <p>Unfortunately the most obvious candidate, the method <code>appendtext()</code> only works for plain text, not rich text.
  Switching to WPF is currently not an option unfortunately.</p>
  
  <p>Thanks!</p>