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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  Windows 3.1 only
 
  CDC* GetDCEx( CRgn* prgnClip, DWORD flags );
 
  Parameter   Description
 
  <prgnClip>  Identifies a clipping region that may be combined with the
              visible region of the client window.
 
  <flags>     Can have one of the following preset values:
 
              Value                  Meaning
 
              DCX_CACHE              Returns a device context from the
                                     cache, rather than the OWNDC or
                                     CLASSDC window. Essentially overrides
                                     CS_OWNDC and CS_CLASSDC.
 
              DCX_CLIPCHILDREN       Excludes the visible regions of all
                                     child windows below the CWnd window.
 
              DCX_CLIPSIBLINGS       Excludes the visible regions of all
                                     sibling windows above the CWnd
                                     window.
 
              DCX_EXCLUDERGN         Excludes the clipping region
                                     identified by <prgnClip> from the
                                     visible region of the returned device
                                     context.
 
              DCX_INTERSECTRGN       Intersects the clipping region
                                     identified by <prgnClip> within the
                                     visible region of the returned device
                                     context.
 
              DCX_LOCKWINDOWUPDATE   Allows drawing even if there is a
                                     LockWindowUpdate call in effect that
                                     would otherwise exclude this window.
                                     This value is used for drawing during
                                     tracking.
 
              DCX_PARENTCLIP         Uses the visible region of the parent
                                     window, ignoring the parent window's
                                     WS_CLIPCHILDREN and WS_PARENTDC style
                                     bits. This value sets the device
                                     context's origin to the upper-left
                                     corner of the CWnd window.
 
              DCX_WINDOW             Returns a device context
                                     corresponding to the window rectangle
                                     rather than the client rectangle.
 
  Remarks
 
  Retrieves the handle of a device context for the CWnd window. The device
  context can be used in subsequent graphics device interface (GDI)
  functions to draw in the client area.
 
  This function, which is an extension to the ◄GetDC► function, gives an
  application more control over how and whether a device context for a
  window is clipped.
 
  Unless the device context belongs to a window class, the ◄ReleaseDC►
  function must be called to release the context after drawing. Since only
  five common device contexts are available at any given time, failure to
  release a device context can prevent other applications from accessing a
  device context.
 
  In order to obtain a cached device context, an application must specify
  ◄DCX_CACHE►. If ◄DCX_CACHE► is not specified and the window is neither
  CS_OWNDC nor ◄CS_CLASSDC►, this function returns NULL.
 
  A device context with special characteristics is returned by the
  ◄GetDCEx► function if the ◄CS_CLASSDC►, ◄CS_OWNDC►, or ◄CS_PARENTDC►
  style was specified in the ◄WNDCLASS► structure when the class was
  registered. For more information about these characteristics, see the
  description of the ◄WNDCLASS► structure.
 
  Return Value
 
  The device context for the specified window, if the function is
  successful. Otherwise, it is NULL.
 
  See Also
 
  ◄CWnd::BeginPaint►, ◄CWnd::GetDC►, ◄CWnd::GetWindowDC►,
  ◄CWnd::ReleaseDC►, ◄::GetDCEx►
 
 
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