Components for Delphi and C++ Builder.

procedure TForm1.DBGridEh1Columns3GetCellParams(Sender: TObject;
  EditMode: Boolean; Params: TColCellParamsEh);
begin
  if MemTableEh1.FieldByName('Continent').AsString = 'South America' then
    Params.Text := FormatFloat(',.0000', (Sender as TColumnEh).Field.AsFloat)
  else
    Params.Text := FormatFloat('.00', (Sender as TColumnEh).Field.AsFloat);
end;