title: Why does my WinForms UserControl stop firing Paint events when BorderStyle = None?
body: <p>I've just tracked down a problem, where one one of my UserControls mysteriously stopped firing Paint events.</p>
  
  <p>Turns out the BorderStyle had been accidently set to None.  When I set it back to FixedSingle, the Paint events started firing again.</p>
  
  <p>This surprised the heck out of me - any idea why this is happening?</p>
  
  <p><strong>edit</strong>
  The UserControl is based on a 3rd party control <a href="http://www.advsofteng.com/cdnet.html" rel="nofollow noreferrer">(ASE ChartDirector)</a>, and we had another problem with it.  When it's BackColor was set to Transparent, it would fire Paint events <strong>continuously</strong>!. The workaround in that case was to set BackColor to ControlLightLight.
  <a href="https://stackoverflow.com/questions/2512249/winforms-tabcontrol-causing-spurious-paint-events-for-usercontrol">(see this question for more details)</a></p>
  
  <p>Could that also be a clue to the BorderStyle problem?</p>