Question

For example, we have event that will go every 3 month. Event have DateStart, DataEnd and Periodicity.

Help me to write method that return true/false if event will go at specific date.

public bool MonthPeriodicityChecker (DateTime start, DateTime end, DateTime dateCheck, int periodicity)
{

}

For example, record have:

start = 02/23/2012 22:00:00;
end = 12/31/2012 23:30:00;
periodicity = 3;

Method must return true when current month = February, May, August, November.

Thanks.

Answer 1

The code is pretty simple:

var someDate = DateTime.Now; // could be any date set some other way

if(someDate > end) return false;

var checkDate = start;
while(checkDate < end)
{
    if(checkDate.Month == someDate.Month && checkDate.Year == someDate.Year)
        return true;
    checkDate = checkDate.AddMonths(periodicity);
}

return false;

All you’re doing is making sure someDate isn’t past end and that the difference in months between the start and someDate is divisible evenly by the periodicity.