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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  afx_msg void OnSysKeyUp( UINT  nChar, UINT  nRepCnt, UINT  nFlags  );
 
  Parameter   Description
 
  <nChar>     Specifies the virtual-key code of the key being pressed.
 
  <nRepCnt>   Specifies the repeat count.
 
  <nFlags>    Specifies the scan code, key-transition code, previous key
              state, and context code, as shown in the following list:
 
              Value   Description
 
              0-7     Scan code (OEM-dependent value). Low byte of
                      high-order word.
 
              8       Extended key, such as a function key or a key on the
                      numeric keypad (1 if it is an extended key;
                      otherwise 0).
 
              9-10    Not used.
 
              11-12   Used internally by Windows.
 
              13      Context code (1 if the ALT key is held down while
                      the key is pressed, 0 otherwise).
 
              14      Previous key state (1 if the key is down before the
                      message is sent, 0 if the key is up).
 
              15      Transition state (1 if the key is being released, 0
                      if the key is being pressed).
 
              For OnSysKeyUp calls, the key-transition bit (bit 15) is 1.
              The context-code bit (bit 13) is 1 if the ALT key is down
              while the key is pressed; it is 0 if the message is sent to
              the active window because no window has the input focus.
 
  Remarks
 
  If the CWnd has the focus, the OnSysKeyUp member function is called when
  the user releases a key that was pressed while the ALT key was held
  down. If no window currently has the input focus, the active window's
  OnSysKeyUp member function is called. The CWnd that receives the call
  can distinguish between these two contexts by checking the context code
  in <nFlags>.
 
  When the context code is 0, the WM_SYSKEYUP message received by
  OnSysKeyUp can be passed to the ◄TranslateAccelerator► Windows function,
  which will handle it as though it were a normal key message instead of a
  system-key message. This allows accelerator keys to be used with the
  active window even if the active window does not have the input focus.
 
  For IBM Enhanced 101- and 102-key keyboards, enhanced keys are the right
  ALT and the right CONTROL keys on the main section of the keyboard; the
  INSERT, DELETE, HOME, END, PAGE UP, PAGE DOWN, and ARROW keys in the
  clusters to the left of the numeric keypad; and the slash (/) and ENTER
  keys in the numeric keypad. Some other keyboards may support the
  extended-key bit in <nFlags>.
 
  For non-USA Enhanced 102-key keyboards, the right ALT key is handled as
  a CONTROL-ALT key. The following shows the sequence of messages and
  calls that result when the user presses and releases this key:
 
  Sequence   Function            Message passed
             accessed
 
  1.         ◄WM_KEYDOWN►        VK_CONTROL
 
  2.         ◄WM_KEYDOWN►        VK_MENU
 
  3.         ◄WM_KEYUP►          VK_CONTROL
 
  4.         ◄WM_SYSKEYUP►       VK_MENU
 
  This message-handler member function calls the ◄Default► member
  function. Override this member function in your derived class to handle
  the ◄WM_SYSKEYUP► message.
 
  See Also
 
  ◄::TranslateAccelerator►, ◄WM_SYSKEYDOWN►, ◄CWnd::Default►,
  ◄WM_SYSKEYUP►
 
 
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