Question:
How can I globally trap the Windows system key "PrintScreen"?
Answer:
The following example demonstrates registering a hot key with the
system to globally trap the windows printscreen key.
Example:
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
private
{ Private declarations }
procedure WMHotKey(var Msg : TWMHotKey); message WM_HOTKEY;
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
const id_SnapShot = 101;
procedure TForm1.WMHotKey (var Msg : TWMHotKey);
begin
if Msg.HotKey = id_SnapShot then
ShowMessage('GotIt');
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
RegisterHotKey(Form1.Handle,
id_SnapShot,
0,
VK_SNAPSHOT);
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
UnRegisterHotKey (Form1.Handle, id_SnapShot);
end;