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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  BOOL GetUpdateRect( LPRECT lpRect, BOOL bErase = FALSE );
 
  Parameter   Description
 
  <lpRect>    Points to a CRect or ◄RECT► structure that is to receive the
              client coordinates of the update enclosing the update
              region.
 
  <bErase>    Specifies whether the background in the update region is to
              be erased.
 
  Remarks
 
  Retrieves the coordinates of the smallest rectangle that completely
  encloses the update region. If CWnd was created with the CS_OWNDC style
  and the mapping mode is not MM_TEXT, the GetUpdateRect member function
  gives the rectangle in logical coordinates. Otherwise, GetUpdateRect
  gives the rectangle in client coordinates. If there is no update region,
  GetUpdateRect sets the rectangle to be empty (sets all coordinates to
  0).
 
  The <bErase> parameter specifies whether GetUpdateRect should erase the
  background of the update region. If <bErase> is TRUE and the update
  region is not empty, the background is erased. To erase the background,
  GetUpdateRect sends the ◄WM_ERASEBKGND► message.
 
  The update rectangle retrieved by the ◄BeginPaint► member function is
  identical to that retrieved by the GetUpdateRect member function.
 
  The ◄BeginPaint► member function automatically validates the update
  region, so any call to GetUpdateRect made immediately after a call to
  ◄BeginPaint► retrieves an empty update region.
 
  Return Value
 
  Specifies the status of the update region. The value is TRUE if the
  update region is not empty; otherwise FALSE.
 
  See Also
 
  ◄CWnd::BeginPaint►, ◄::GetUpdateRect►
 
 
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