if (DateTimePicker1.Text<>'') and (DateTimePicker2.Text<>'') then begin
Query1.Sql.Add(' And 日期 between '''+ DateTimePicker1.Text +''' and '''+ DateTimePicker2.Text + '''');
end;
Query1.Sql.Add(' And 日期 between '''+ DateTimePicker1.Text +''' and '''+ DateTimePicker2.Text + '''');
end;
FormatDateTime('YYYY"-"MM"-"DD', DateTimePicker1.Date) +''' and '''+
FormatDateTime('YYYY"-"MM"-"DD', DateTimePicker2.Date) + '''');