Article #17091: Shift, Ctrl, Alt key checking

 Question and Answer Database
FAQ2091D.txt Shift, Ctrl, Alt key checking
Category :VCL
Platform :All
Product :All 32 bit
Question:
How can I determine if the Shift, Alt, or Ctrl key is
depressed at any given time?
Answer:
The following example demonstrates checking if the Shift key is
pressed during a menu item selection. The example presents
functions for testing the status of the Alt, Ctrl, and
shift keys.
Example:
function CtrlDown : Boolean;
var
State : TKeyboardState;
begin
GetKeyboardState(State);
Result := ((State[vk_Control] And 128) <> 0);
end;
function ShiftDown : Boolean;
var
State : TKeyboardState;
begin
GetKeyboardState(State);
Result := ((State[vk_Shift] and 128) <> 0);
end;
function AltDown : Boolean;
var
State : TKeyboardState;
begin
GetKeyboardState(State);
Result := ((State[vk_Menu] and 128) <> 0);
end;
procedure TForm1.MenuItem12Click(Sender: TObject);
begin
if ShiftDown then
Form1.Caption := 'Shift' else
Form1.Caption := '';
end;
7/16/98 4:31:28 PM

Last Modified: 01-SEP-99