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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  afx_msg void OnSysKeyDown( 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 OnSysKeyDown calls, the key-transition bit (bit 15) is
              0. 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 input focus, the OnSysKeyDown member function is
  called when the user holds down the ALT key and then presses another
  key. If no window currently has the input focus, the active window's
  OnSysKeyDown member function is called. The CWnd that receives the
  message can distinguish between these two contexts by checking the
  context code in <nFlags>.
 
  When the context code is 0, the WM_SYSKEYDOWN message received by
  OnSysKeyDown 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.
 
  Because of auto-repeat, more than one OnSysKeyDown call may occur before
  the ◄WM_SYSKEYUP► message is received. The previous key state (bit 14)
  can be used to determine whether the OnSysKeyDown call indicates the
  first down transition or a repeated down transition.
 
  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>.
 
  This message-handler member function calls the ◄Default► member
  function. Override this member function in your derived class to handle
  the ◄WM_SYSKEYDOWN► message.
 
  See Also
 
  ◄::TranslateAccelerator►, ◄WM_SYSKEYUP►, ◄CWnd::Default►,
  ◄WM_SYSKEYDOWN►
 
 
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