Various quarter-related DateTime functions in C#

The DateTime object – or struct – lacks functions for quarters. You can e.g. add minutes, months, days etc. to a date but not quarters.

Here comes a short list of simple quarter-related functions.

Add quarters to a date:

public DateTime AddQuarters(DateTime originalDate, int quarters)
{
	return originalDate.AddMonths(quarters * 3);
}

Example:

DateTime future = AddQuarters(DateTime.UtcNow, 2);

Get the quarter number of a date:

public int GetQuarter(DateTime fromDate)
{
	int month = fromDate.Month - 1;
	int month2 = Math.Abs(month / 3) + 1;
	return month2;
}

Usage:

int quarter = GetQuarter(DateTime.UtcNow);

Get first and last day of a quarter:

public DateTime GetFirstDayOfQuarter(DateTime originalDate)
{			
	return AddQuarters(new DateTime(originalDate.Year, 1, 1), GetQuarter(originalDate) - 1);
}

public DateTime GetLastDayOfQuarter(DateTime originalDate)
{
	return AddQuarters(new DateTime(originalDate.Year, 1, 1), GetQuarter(originalDate)).AddDays(-1);
}

Usage:

DateTime first = GetFirstDayOfQuarter(DateTime.UtcNow);
DateTime last = GetLastDayOfQuarter(DateTime.UtcNow);

View all various C# language feature related posts here.