procedure TForm1.FormClick(Sender: TObject);
var
R : HRgn;
begin
if IsRound then
begin
SetWindowRgn(Handle,0,True);
DeleteObject(R);
IsRound := False;
end else
begin
R := CreateEllipticRgn(-15,-15,Width+15,Height+15);
SetWindowRgn(Handle,R,True);
IsRound := True;
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
IsRound := False;
end;
end.