82 lines
3.7 KiB
HTML
82 lines
3.7 KiB
HTML
<HTML>
|
|
<HEAD><TITLE>QuickBASIC 3.0 - Long Entry</TITLE></HEAD>
|
|
<BODY>
|
|
|
|
<A HREF="ng16339.html">[<<Previous Entry]</A>
|
|
<A HREF="ng320.html">[^^Up^^]</A>
|
|
<A HREF="ng16dd7.html">[Next Entry>>]</A>
|
|
<A HREF="menu.html" >[Menu]</A>
|
|
<A HREF="info.html">[About The Guide]</A>
|
|
<HR>
|
|
<PRE>
|
|
<B>KEY Set or Display Soft Keys</B>
|
|
|
|
<B>KEY</B> {ON | OFF | LIST}
|
|
<B>KEY</B> <U>n</U>, <U>strexpr</U>
|
|
<B>KEY</B> <U>n</U>, CHR$(<U>KBflag</U>) + CHR$(<U>scancode</U>)
|
|
|
|
Controls the display and contents of the function keys F1 through F10;
|
|
allows trapping of any scan code in any shift state.
|
|
|
|
ON KEY ON enables the display, on line 25, of current
|
|
function key settings. Only the first six character
|
|
assigned to each function key are displayed. If the screen
|
|
is in an 80-column display mode, all ten function keys are
|
|
displayed; if it's in a 40-column mode, the first five are
|
|
displayed. KEY ON is the default setting in BASIC.
|
|
|
|
OFF KEY OFF removes the function key display from line 25,
|
|
making line 25 available for other purposes. With KEY OFF
|
|
in effect, a LOCATE 25,<U>n</U> can be used to display other text
|
|
at the bottom of the screen. Line 25 does not scroll, but
|
|
it is erased by a CLS statement.
|
|
|
|
LIST KEY LIST displays the current soft key definitions on
|
|
screen.
|
|
|
|
<U>n</U>, <U>strexpr</U> KEY <U>n</U>, <U>strexpr</U> assigns the string expression <U>strexpr</U> to
|
|
function key <U>n</U>. <U>n</U> is a numeric expression in the range 1
|
|
to 10. Only the first 15 characters of <U>strexpr</U> are
|
|
significant. A null string <U>strexpr</U> deactivates the
|
|
associated function key.
|
|
|
|
<U>n</U>, CHR$(<U>KBflag</U>) + CHR$(<U>scancode</U>)
|
|
The statement KEY <U>n</U>, CHR$(<U>KBflag</U>) + CHR$(<U>scancode</U>) enables
|
|
your program to trap specified Ctrl keys, Alt keys, and
|
|
Shifted keys. <U>n</U> is a numeric expression in the range 15 to
|
|
20 (up to six traps may be in effect at once). <U>KBflag</U>,
|
|
which must be expressed in hexadecimal, specifies the
|
|
shift state of the key to be trapped, and scancode
|
|
specifies which alphanumeric key is to be trapped.
|
|
|
|
The following options are available for <U>KBflag</U>:
|
|
|
|
&H40 Caps Lock active
|
|
&H20 Num Lock active
|
|
&H08 Alt key pressed
|
|
&H04 Ctrl key pressed
|
|
&H02 Left Shift key pressed
|
|
&H01 Right Shift key pressed
|
|
&H00 Caps Lock inactive, Num Lock inactive
|
|
|
|
These options may be used in additive fashion, to trap
|
|
combinations of shift states. For example,
|
|
CHR$(&H08+&H02+&H01) would catch the combination of the
|
|
Alt key with either (or both) Shift keys.
|
|
|
|
Trapped keys do not enter the BIOS keyboard buffer.
|
|
Therefore, if either Ctrl-Break or Ctrl-Alt-Del is
|
|
trapped, there will be no way (other than powering down)
|
|
to break out of an infinite loop.
|
|
</PRE>
|
|
<HR>
|
|
<B>See Also:</B>
|
|
<A HREF="ng16dd7.html">KEY(n)</A>
|
|
<A HREF="ng1e384.html">ON KEY</A>
|
|
<HR>
|
|
This page created by ng2html v1.05, the Norton guide to HTML conversion utility.
|
|
Written by <A HREF="http://www.acemake.com/hagbard">Dave Pearson</A>
|
|
<HR>
|
|
</BODY>
|
|
</HTML>
|