Nearest completed quarter

Question

Is there a C# function which will give me the last day of the most recently finished Quarter given a date?

For example,

var lastDayOfLastQuarter = So         


        

Answer 1

Assuming quarters always end at 3 month intervals you could do:

Maybe not the best solution, but very easy to read and modify compared to other solutions offered.

public DateTime LastDayOfLastQuarter(DateTime date)
{
    int result = (int)(date.Month/3)

    switch (result)
    {
        // January - March
        case 0:
            return new DateTime(date.Year - 1, 12, 31);
        // April - June
        case 1:
            return new DateTime(date.Year, 3, 31);
        // July - September
        case 2:
            return new DateTime(date.Year, 6, 30);
        // October - December
        case 3:
            return new DateTime(date.Year, 9, 30);
    }
}