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...detect more than 2 keys being pressed within a form?
Autor: Radikal, Q3 Team
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Tip Rating (27):  
     


{
  I would like to detect more than 2 keys being pressed within a form.
  For example I would like to know if the user pressed    time. The onkeydown seems to only check for one or two keys max but surely
  you can determine what keys are currently down.
}

// You can use GetKeyState:

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  If 
((GetKeyState(VK_CONTROL) AND 128)=128) and
     
((GetKeyState(VK_F5)      AND 128)=128) and
     
((GetKeyState(ord('8'))   AND 128)=128)
    then
      
ShowMessage('CTRL+F5+8 Pressed');
end;

( Remember: Form1.Keypreview := TRUE )


// Or you can read the entire KeyBoard Status,
// and later check for the three keys:

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var
   
KeybState: TKeyboardState;
begin
  
GetKeyboardState(Teclado);
  If ( (KeybState[VK_CONTROL] and 128)=128 ) and
     
( (KeybState[VK_F5]      and 128)=128 ) and
     
( (KeybState[Ord('8')]   and 128)=128 )
    then
      
ShowMessage('CTRL+F5+8 Pressed');
end;


 

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