   Invalidate() win32 calls base form OnPaints?
  I have a base form with a background image.The WM_PAINT events occur as follows.MainForm.OnPaintBackground() clip area 1280x1024MainForm.OnPaint() clip 1280x1024then I load a control and call invalidate()thus causesMainForm.OnPaintBackground() clip area 100x100MainForm.OnPaint() clip 100x100UserControl.OnPaint() clip 100x100Can't I just invalidate the control and not the form?I don't need to repaint the MainForm just the area of the control.   
  What does your invalidate look like?What you'll want to do is set the Erase State to false so you don't call WM_ERASEBKGRND, and set the parent to have WS_CLIPCHILDREN.   ;  It also seems you Must override the OnPaintBackground and OnPaint for the Usercontrol and the BaseForm . I was only overriding the OnPaint for both, and the OnPaintBackground for the BaseForm.This corrected the problem. Thanks again!   