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Declaring User-Defined Keys
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Declaring User-Defined Keys
■ In addition to providing the pre-assigned key numbers 1-14 (plus 30 and 31
with the 101-key keyboard), Visual Basic allows you to create user-defined
keys.
■ User-defined keys can be assigned to the numbers 15-25 or to any other
unused keys on the keyboard. See: ◄KEY Statement (Assignment)►
■ You can also set a trap for "shifted" keys. A key is shifted when you
press it simultaneously with one or more of the special keys Shift, Ctrl,
or Alt, or if you press it after pressing NumLock or Caps Lock. Use the
KEY statement to define shifted keys before you can trap them.
■ You can add the values in the Keyboard Flag Table together to test for
multiple shift states. A keyboard flag value of 12 would test for both
Ctrl and Alt being pressed. See: ◄Keyboard Flag Table►
■ To define Shift, Ctrl, Alt, NumLock, or Caps Lock as a user-defined key
(by itself, not in combination with another key), use a keyboard flag of
0. For example, to define Alt as a user-defined key:
KEY CHR$(0) + CHR$(56)
■ To define Alt+Alt as a user-defined key:
KEY CHR$(8) + CHR$(56)
Note: The second Alt will be trapped as it is pressed only if the first
Alt key is already pressed.
■ Because key trapping assumes the left and right Shift keys are the same,
you can use either 1, 2, or 3 to indicate a Shift key. The scancode
argument is a number identifying one of the 83 keys to trap, as shown in
the scan code table. See: ◄Keyboard Scan Codes►