[ecfisa]

Hola.

Código Delphi [-]
procedure TForm1.SpeedButton1Click(Sender: TObject);
var
  ed: TEdit;
begin
  if ActiveControl is TEdit then
  begin
    ed := TEdit(ActiveControl);
    ed.Text := IntToSTr(StrToIntDef(ed.Text,0)+1);
  end;
end;

Saludos