Dates.Recurring
Easily calculate the next time at which a recurring event occurs. Uses a fluent syntax.
Install
PM> Install-Package Dates.Recurring
Calculate the next occurrence of a recurring date.
// Daily recurrences
var daily = Recurs
.Starting(new DateTime(2015, 1, 1))
.Every(1)
.Days()
.Ending(new DateTime(2015, 1, 15))
.Build();
daily.Next(new DateTime(2014, 7, 3)); // 2015/01/01
daily.Next(new DateTime(2015, 1, 1)); // 2015/01/02
daily.Next(new DateTime(2015, 1, 2)); // 2015/01/03
daily.Next(new DateTime(2015, 1, 15)); // null
// Weekly recurrences
var weekly = Recurs
.Starting(new DateTime(2015, 1, 1))
.Every(1)
.Weeks()
.OnDays(Day.TUESDAY | Day.FRIDAY)
.Ending(new DateTime(2015, 2, 19))
.Build();
weekly.Next(new DateTime(2014, 1, 1); // 2015/01/02
weekly.Next(new DateTime(2015, 1, 2); // 2015/01/06
weekly.Next(new DateTime(2014, 1, 6); // 2015/01/09
weekly.Next(new DateTime(2014, 1, 9); // 2015/01/13
// Monthly recurrences
var monthly = Recurs
.Starting(new DateTime(2015, 1, 1))
.Every(1)
.Months()
.OnDay(24)
.Ending(new DateTime(2016, 2, 4))
.Build();
monthly.Next(new DateTime(2014, 4, 8); // 2015/01/24
monthly.Next(new DateTime(2015, 1, 24); // 2015/02/24
monthly.Next(new DateTime(2015, 2, 24); // 2015/03/24
monthly.Next(new DateTime(2015, 2, 10); // 2015/03/24
// Yearly recurrences
var yearly = Recurs
.Starting(new DateTime(2015, 1, 1))
.Every(1)
.Years()
.OnDay(24)
.OnMonths(Month.JANUARY | Month.FEBRUARY | Month.AUGUST)
.Ending(new DateTime(2020, 1, 1))
.Build();
yearly.Next(new DateTime(2014, 1, 1)); // 2015/01/24
yearly.Next(new DateTime(2015, 1, 1)); // 2015/01/24
yearly.Next(new DateTime(2015, 1, 23)); // 2015/01/24
yearly.Next(new DateTime(2014, 1, 24)); // 2015/02/24
yearly.Next(new DateTime(2014, 2, 24)); // 2015/08/24