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KeyDown, KeyUp Events Details
  Summary  Details  Example                Contents  Index  Back
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 SUB Form_KeyDown (KeyCode AS INTEGER, Shift AS INTEGER)
 SUB ctlname_KeyDown ([Index AS INTEGER,]KeyCode AS INTEGER,
                       Shift AS INTEGER)
 SUB Form_KeyUp (KeyCode AS INTEGER, Shift AS INTEGER)
 SUB ctlname_KeyUp ([Index AS INTEGER,]KeyCode AS INTEGER, Shift AS INTEGER)
 
 Usage Notes
   ■ Use KeyDown and KeyUp event procedures to handle keyboard routines when
     forms are showing. The ON KEY statement will not work when forms are
     showing.
 
   ■ For both KeyDown and KeyUp events, the object with the focus receives
     all keystrokes, but a form can have the focus only if it has no visible
     or enabled controls. See: Focus Definition
 
   ■ KeyCode values for ASCII-printable keys (A-Z, a-z, 0-9, ~, [, ], {, },
     +, =) are the same as their ASCII equivalents. In Visual Basic for DOS,
     the returned KeyCode value differentiates between uppercase and
     lowercase, and returns the same value as the KeyAscii parameter used in
     the KeyPress event procedure. See: KeyPress Event
 
   ■ Use shortcut and access keys for keyboard shortcuts instead of code
     that responds to KeyDown and KeyUp events; these keys require no
     additional code. You can program these keys when creating menus in the
     Form Designer.
 
   ■ Although KeyDown and KeyUp events can detect all keys, they are most
     often used for:
     • Extended character keys such as function keys
     • Navigation keys
     • Combinations of the Shift, Ctrl, and Alt keys (keyboard modifiers)
     • Distinguishing between the numeric keypad and regular number keys
 
   ■ Use KeyDown and KeyUp event procedures to write keyboard handlers if you
     want your application to respond to both the press and release of a key.
 
   ■ KeyDown and KeyUp are not invoked for the following keys and conditions:
 
     Key        Condition
     ═════════  ════════════════════════════════════════════════════════════
     Enter      If the form has a command button with the Default property
                set to True (-1)
     Esc        If the form has a command button with the Cancel property
                set to True (-1)
     Tab        If two or more controls are on the form