public static DateTime GetRelativeDate(int year, int month, RelativeDayInMonth relativeDay, DayOfWeek day)
{
var monthBegin = new DateTime(year, month, 1);
var firstDay = GetNextWeekday(monthBegin, day);
switch (relativeDay)
{
case RelativeDayInMonth.First:
return(firstDay);
case RelativeDayInMonth.Second:
return(firstDay.AddDays(7));
case RelativeDayInMonth.Third:
return(firstDay.AddDays(14));
case RelativeDayInMonth.Fourth:
return(firstDay.AddDays(21));
case RelativeDayInMonth.Last:
var totalDays = DateTime.DaysInMonth(year, month);
return(firstDay.AddDays(Math.Floor((totalDays - firstDay.Day) / 7d) * 7));
default:
throw new ArgumentOutOfRangeException();
}
}
public void TestGetRelativeDate(int year, int month, RelativeDayInMonth relativeDay, DayOfWeek day, int expectedDay)
{
var result = ScheduledTriggerService.GetRelativeDate(year, month, relativeDay, day);
Assert.Equal(year, result.Year);
Assert.Equal(month, result.Month);
Assert.Equal(expectedDay, result.Day);
}
