Dos decimales en un Edit

[[cHackAll]]

Código Delphi [-]
procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);
var pos: Cardinal;
begin
 with Sender as TEdit do
  begin
   pos := System.Pos(',', Text);
   if not LongBool(Pos) then Dec(Pos);
   ReadOnly := not (Key in ['0'..'9', ',', #8]) or
               (Pos <> $FFFFFFFF) and (Key = ',') or
               ((Key <> #8) and (Pos < (SelStart - 1)));
  end;
end;