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CTRL Down/Up ????

steff
steff asked
on
Medium Priority
533 Views
Last Modified: 2008-02-01
Hi

I would like to know if it is possible to aks Delphi/Windows for the current state of the Shift, Alt and Ctrl keys. I emagine something like:

function GetCurrentShiftState: TShiftState;

...and the use it like...

...
SS : TShiftState;
...
SS := GetCurrentShiftState;
...

Exactly what I want to do is on a given time to be able find out if the Ctrl-button is up og down.
Can anyone please help me solve my problem.

Thanx - Steff
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Commented:
Hi steff,

You can get the keyboard state in a timer with, say, 100 ms interval. I j

       VAR KS : TKeyboardState;
       ...
       GetKeyboardState(KS);
       IF Odd(KS[VK_CAPITAL]) THEN {caps lock is down}
       ... VK_NUMLOCK
       ... VK_SCROLL
       ... VK_INSERT

Zif.

Commented:
i believe you should use VK_Control.

Author

Commented:
Hi ZifNab

I'm not sure I understand what you mean - would you please explain alittle more.

Steff

Author

Commented:
Hi ZifNab

I'm not sure I understand what you mean - would you please explain alittle more.

Steff
Commented:
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Author

Commented:
Hi Zif

Thanx alot for your answer. What I actualy got out of it was that I got to know the function GetKeyboardState and the type TKeyboardState - I didn't know them before.

I guess that a general problem for me is that I dont know enough about Windows-programming. Can you tell me how I can get a good .hlp file on windows-programming?

Am I right when I say that it is alittle strange that online help in Delphi says nothing about the functions that it ofers to windows - e.g. GetKeyboardState?
If it had just metioned it I would have found it in there - but the again, you would not have had this question at the following points  ;-)

BTW I think that your second idea...

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
begin
if (ssCtrl in shift) then
ShowMessage('Ctrl is pressed');
end;

.would not have worked for me, since I can not be sure that the user pushes the CTRL-key when my application is active. What if the user pushes the CTRL key down, holds it down and then activates my application. If he now does the thing that makes me want to know if CTRL is down, I would (by this method) know that the CTRL-key actualy is down !?!?!?

Thanx Steff

Commented:
Yep, delphi manual has some lacks... sorry, don't know od a very good .hlp file. Everything I know of these functions is because I somewhere found them on the net.

About ctrl-key. I don't know if second idea works, haven't tried it the way you propose it.

Zif.
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