/// <summary>
/// This is used to find the starting point for the secondly frequency
/// </summary>
/// <param name="r">A reference to the recurrence</param>
/// <param name="start">The recurrence start date</param>
/// <param name="end">The recurrence end date</param>
/// <param name="from">The start date of the range limiting the instances generated</param>
/// <param name="to">The end date of the range limiting the instances generated</param>
/// <returns>The first instance date or null if there are no more instances</returns>
public RecurDateTime FindStart(Recurrence r, RecurDateTime start, RecurDateTime end, RecurDateTime from,
RecurDateTime to)
{
RecurDateTime rdt = new RecurDateTime(start);
int adjust;
if (RecurDateTime.Compare(start, from, RecurDateTime.DateTimePart.Hour) < 0)
{
// Get the difference between the recurrence start and the limiting range start
DateTime dtStart = start.ToDateTime(), dtFrom = from.ToDateTime();
// Adjust the date/time so that it's in range
TimeSpan ts = dtFrom - dtStart;
adjust = (int)ts.TotalSeconds + r.Interval - 1;
rdt.AddSeconds(adjust - (adjust % r.Interval));
}
if (RecurDateTime.Compare(rdt, end, RecurDateTime.DateTimePart.Hour) > 0 ||
RecurDateTime.Compare(rdt, to, RecurDateTime.DateTimePart.Hour) > 0)
{
return(null);
}
return(rdt);
}
/// <summary>
/// This is used to find the next instance of the secondly frequency
/// </summary>
/// <param name="r">A reference to the recurrence</param>
/// <param name="end">The recurrence end date</param>
/// <param name="to">The end date of the range limiting the instances generated</param>
/// <param name="last">This is used to pass in the last instance date calculated and return the next
/// instance date</param>
/// <returns>True if the recurrence has another instance or false if there are no more instances</returns>
public bool FindNext(Recurrence r, RecurDateTime end, RecurDateTime to, RecurDateTime last)
{
last.AddSeconds(r.Interval);
if (last > end || last > to)
{
return(false);
}
return(true);
}