请问数据库控件的 BookMark（书签）属性是什么意思，如何使用？

Question

用getbook(),gotobook(),freebook()纪录某条纪录位置，以后返回这条纪录，释放资源

Answer 1

procedure TForm1.SelectClick(Sender: TObject);
var  x: word;
  TempBook: TBookMark;
begin
  DBGrid1.Datasource.Dataset.DisableControls;
  with DBgrid1.SelectedRows do
  if Count > 0 then
  begin
    TempBook:= DBGrid1.Datasource.Dataset.GetBook;
    for x:= 0 to Count - 1 do
    begin
      if IndexOf(Items[x]) > -1 then
      begin
        DBGrid1.Datasource.Dataset.Book:= Items[x];
        showmessage(DBGrid1.Datasource.Dataset.Fields[1].AsString);
      end;
    end;
    DBGrid1.Datasource.Dataset.GotoBook(TempBook);    DBGrid1.Datasource.Dataset.FreeBook(TempBook);
  end;
  DBGrid1.Datasource.Dataset.EnableControls;
end;