asked on

Keyboard Lights

I wonder how i can get the "Keyboard Ligths"
(NUM LOCK/CAPS LOCK/SCREEN LOCK) to all be turned on...

ASKER CERTIFIED SOLUTION

DragonSlayer

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sundayboys

function IsNumLockOn: boolean;
var KeyState: TKeyboardState;
begin
GetKeyboardState(KeyState);
Result := (KeyState[VK_NUMLOCK] and 1) = 1;
end;

procedure NumLockOn;
var KeyState: TKeyboardState;
begin
GetKeyboardState(KeyState);
KeyState[VK_NUMLOCK] := $01;
SetKeyboardState(KeyState);
end;

procedure NumLockOff;
var KeyState: TKeyboardState;
begin
GetKeyboardState(KeyState);
KeyState[VK_NUMLOCK] := $00;
SetKeyboardState(KeyState);
end;

// these tips can use with other keys ie. VK_CAPITAL, VK_SCROLL

DragonSlayer

SundayBoys,

From the Win32 API help file:

Because the SetKeyboardState function alters the input state of the calling thread and not the global input state of the system, an application cannot use SetKeyboardState to set the NUM LOCK, CAPS LOCK, or SCROLL LOCK indicator lights on the keyboard.

DragonSlayer.

sundayboys

DragpmSlayer?F
try my code,it can change NUMLOCK lights.my OS is win98se.
Don't always trust Microsoft!

DragonSlayer

sundayboys

:-)

robert_marquardt

I think the code does not only sets the numlock light but also the numlock state!
The problem is that Windows now has a virtual system keyboard and you cannot fiddle with the keyboard controller anymore. It may be that your oly keyboard is USB which is not controlled by the keyboard controller.

Madshi

We needed to control the LEDs (including the state) in win9x in our firm, too. We worked hard on that and finally found a method which works more or less reliable. But it works only in connection with our little keyboard driver.

We also tried the SetKeyboardState stuff, of course, but somehow it made problems. I don't remember exactly, what the problem was. I think, it was not reliable, on some keyboards it did work, on others it did not.

Regards, Madshi.

Dennis9

hi.
Something like this?

procedure TurnAllOn;
var
keys: TKeyboardState;
begin
GetKeyboardState( keys );
keys[VK_NUMLOCK] := 1; {Num Lock}
keys[VK_CAPITAL] := 1; {Caps Lock}
keys[VK_SCROLL] := 1; {Scroll Lock}
SetKeyboardState(keys);
end;

procedure TurnAllOff;
var
keys: TKeyboardState;
begin
GetKeyboardState( keys );
keys[VK_NUMLOCK] := 0; {Num Lock}
keys[VK_CAPITAL] := 0; {Caps Lock}
keys[VK_SCROLL] := 0; {Scroll Lock}
SetKeyboardState(keys);
end;

Dennis

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