Microsoft Foundation Classes (mfc.hlp) (Table of Contents; Topic list)
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CWnd::Invalidate
◄CWnd►                                        ◄Up► ◄Contents► ◄Index► ◄Back►
──Microsoft Foundation Classes──────────────────────────────────────────────
 
  void Invalidate( BOOL bErase = FALSE );
 
  Parameter   Description
 
  <bErase>    Specifies whether the background within the update region is
              to be erased.
 
  Remarks
 
  Invalidates the entire client area of CWnd. The client area is marked
  for painting when the next ◄WM_PAINT► message occurs. The region can
  also be validated before a WM_PAINT message occurs by using the
  ◄ValidateRect► or ◄ValidateRgn► member function.
 
  The <bErase> parameter specifies whether the background within the
  update area is to be erased when the update region is processed. If
  <bErase> is TRUE, the background is erased when the ◄BeginPaint► member
  function is called; if <bErase> is FALSE, the background remains
  unchanged. If <bErase> is TRUE for any part of the update region, the
  background in the entire region is erased, not just in the given part.
 
  Windows sends ◄WM_PAINT► whenever the CWnd update region is not empty
  and there are no other messages in the application queue for that
  window.
 
  See Also
 
  ◄CWnd::BeginPaint►, ◄CWnd::ValidateRect►, ◄CWnd::ValidateRgn►,
  ◄::InvalidateRect►
 
 
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