capslock wide hook

The solution is creating a .dll with a Keyboard hook. I have one installed

on this pc which helps me avoid turning on CapsLock. Beware that I didn't

find a way to stop the CapsLock from being processed, so I had to send

another one ;-)

Here it goes (.Exe file loading the .dll:):

program CapsLock;

{$R *.RES}

uses

Windows;

var

HDLL: HMODULE;

HookAddr: pointer;

const

AHook: HHOOK = 0;

begin

HDLL:=LoadLibrary('keybhook.dll');

if HDLL > HINSTANCE_ERROR then begin

HookAddr:=GetProcAddress(HDLL, 'KeybHookCallback');

if Assigned(HookAddr) then

AHook:=SetWindowsHookEx(WH_KEYBOARD, HookAddr, HDLL, 0);

end;

Sleep(INFINITE);

if AHook > 0 then

UnhookWindowsHookEx(AHook);

if HDLL > HINSTANCE_ERROR then

FreeLibrary(HDLL);

end.

------------

(.dll code):

library KeybHook;

uses

Windows,

Messages,

UHook in 'UHook.pas';

exports

KeybHookCallback;

{$R *.RES}

begin

end.

------------

unit UHook;

interface

uses Windows, Messages, SysUtils;

function KeybHookCallback(Code, wParam, lParam: integer): integer; stdcall;

implementation

const

gFilterCapsLock: boolean = TRUE;

gInSettingCaps: boolean = false;

procedure SetCapsLockState(Value: boolean);

var

KeyState: TKeyboardState;

begin

GetKeyboardState(keyState);

if (Value xor boolean(keyState[VK_CAPITAL])) then begin

gInSettingCaps:=true;

keybd_event(VK_CAPITAL, $45, KEYEVENTF_EXTENDEDKEY, 0);

keybd_event(VK_CAPITAL, $45, KEYEVENTF_EXTENDEDKEY or KEYEVENTF_KEYUP,

0);

end;

end;

function KeybHookCallback(Code, wParam, lParam: integer): integer; stdcall;

var

AKeyFlag: Word;

begin

result:=0;

AKeyFlag:=(lParam shr 16);

if gFilterCapsLock

and (Code = HC_ACTION)

and ((wParam and $FFFF) = VK_CAPITAL) then begin

if ((AKeyFlag and $FF00) = $C100) then // True only when key is sent

from keybd_event

gInSettingCaps:=false

else begin

if not gInSettingCaps then begin

beep;

SetCapsLockState(false);

end;

end;

end

CallNextHookEx(0, Code, wParam, lParam);

end;

end.

--

Regards,

Bj�rge S�ther

bjorge@haha_itte.no