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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  Windows 3.1 only
 
  int ScrollWindowEx( int dx, int dy, const RECT FAR* lpRectScroll,
                      const RECT FAR* lpRectClip, CRgn* prgnUpdate,
                      RECT FAR* lpUpdateRect, UINT flags );
 
  Parameter      Description
 
  <dx>           Specifies the amount, in device units, of horizontal
                 scrolling. This parameter must have a negative value to
                 scroll to the left.
 
  <dy>           Specifies the amount, in device units, of vertical
                 scrolling. This parameter must have a negative value to
                 scroll up.
 
  <lpRectScroll> Points to a RECT structure that specifies the portion of
                 the client area to be scrolled. If this parameter is
                 NULL, the entire client area is scrolled.
 
  <lpRectClip>   Points to a RECT structure that specifies the clipping
                 rectangle to scroll. This structure takes precedence over
                 the rectangle pointed to by <lpRectScroll>. Only bits
                 inside this rectangle are scrolled. Bits outside this
                 rectangle are not affected even if they are in the
                 <lpRectScroll> rectangle. If this parameter is NULL, no
                 clipping is performed on the scroll rectangle.
 
  <prgnUpdate>   Identifies the region that is modified to hold the region
                 invalidated by scrolling. This parameter may be NULL.
 
  <lpUpdateRect> Points to a RECT structure that will receive the
                 boundaries of the rectangle invalidated by scrolling.
                 This parameter may be NULL.
 
  <flags>        Can have one of the following values:
 
                 Value               Meaning
 
                 SW_ERASE            When specified with SW_INVALIDATE,
                                     erases the newly invalidated region
                                     by sending a WM_ERASEBKGND message to
                                     the window.
 
                 SW_INVALIDATE       Invalidates the region identified by
                                     <prgnUpdate> after scrolling.
 
                 SW_SCROLLCHILDREN   Scrolls all child windows that
                                     intersect the rectangle pointed to by
                                     <lpRectScroll> by the number of
                                     pixels specified in <dx> and <dy>.
                                     Windows sends a WM_MOVE message to
                                     all child windows that intersect
                                     <lpRectScroll>, even if they do not
                                     move. The caret is repositioned when
                                     a child window is scrolled and the
                                     cursor rectangle intersects the
                                     scroll rectangle.
 
  Remarks
 
  Scrolls the contents of a window's client area. This function is similar
  to the ◄ScrollWindow► function, with some additional features.
 
  If ◄SW_INVALIDATE► and ◄SW_ERASE► are not specified, the ScrollWindowEx
  member function does not invalidate the area that is scrolled away from.
  If either of these flags is set, ScrollWindowEx invalidates this area.
  The area is not updated until the application calls the ◄UpdateWindow►
  function, calls the ◄RedrawWindow► function (specifying ◄RDW_UPDATENOW►
  or ◄RDW_ERASENOW►), or retrieves the ◄WM_PAINT► message from the
  application queue.
 
  If the window has the ◄WS_CLIPCHILDREN► style, the returned areas
  specified by <prgnUpdate> and <lpUpdateRect> represent the total area of
  the scrolled window that must be updated, including any areas in child
  windows that need updating.
 
  If the ◄SW_SCROLLCHILDREN► flag is specified, Windows will not properly
  update the screen if part of a child window is scrolled. The part of the
  scrolled child window that lies outside the source rectangle will not be
  erased and will not be redrawn properly in its new destination. Use the
  ◄DeferWindowPos► function to move child windows that do not lie
  completely within the <lpRectScroll> rectangle. The cursor is
  repositioned if the ◄SW_SCROLLCHILDREN► flag is set and the caret
  rectangle intersects the scroll rectangle.
 
  All input and output coordinates (for <lpRectScroll>, <lpRectClip>,
  <lpUpdateRect>, and <prgnUpdate>) are assumed to be in client
  coordinates, regardless of whether the window has the ◄CS_OWNDC► or
  ◄CS_CLASSDC► class style. Use the ◄LPtoDP► and ◄DPtoLP► functions to
  convert to and from logical coordinates, if necessary.
 
  Return Value
 
  The return value is SIMPLEREGION (rectangular invalidated region),
  COMPLEXREGION (nonrectangular invalidated region; overlapping
  rectangles), or NULLREGION (no invalidated region), if the function is
  successful. Otherwise, the return value is ERROR.
 
  See Also
 
  ◄CWnd::RedrawWindow►, ◄CDC::ScrollDC►, ◄CWnd::ScrollWindow►,
  ◄CWnd::UpdateWindow►, ◄::ScrollWindowEx►
 
 
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