public override string ToString()
{
var paramList = new List<string>();
if (Format == CronStringFormat.WithSeconds || Format == CronStringFormat.WithSecondsAndYears)
JoinFilters(paramList, CrontabFieldKind.Second);
JoinFilters(paramList, CrontabFieldKind.Minute);
JoinFilters(paramList, CrontabFieldKind.Hour);
JoinFilters(paramList, CrontabFieldKind.Day);
JoinFilters(paramList, CrontabFieldKind.Month);
JoinFilters(paramList, CrontabFieldKind.DayOfWeek);
if (Format == CronStringFormat.WithYears || Format == CronStringFormat.WithSecondsAndYears)
JoinFilters(paramList, CrontabFieldKind.Year);
return string.Join(" ", paramList.ToArray());
}