Date difference in years using C# [duplicate]

Answer 1

The following is based off Dana's simple code which produces the correct answer in most cases. But it did not take in to account less than a year between dates. So here is the code that I use to produce consistent results:

public static int DateDiffYears(DateTime startDate, DateTime endDate)
{
    var yr = endDate.Year - startDate.Year - 1 +
             (endDate.Month >= startDate.Month && endDate.Day >= startDate.Day ? 1 : 0);
    return yr < 0 ? 0 : yr;
}

Answer 2

int Age = new DateTime((DateTime.Now - BirthDateTime).Ticks).Year;

Answer 3

Maybe this will be helpful for answering the question: Count of days in given year,

new DateTime(anyDate.Year, 12, 31).DayOfYear //will include leap years too

Regarding DateTime.DayOfYear Property.

Answer 4

I hope the link below helps

MSDN - DateTime.Subtract.Method (DateTime)

There's even examples for C# there. Just simply click the C# language tab.

Good luck

Answer 5

Use:

int Years(DateTime start, DateTime end)
{
    return (end.Year - start.Year - 1) +
        (((end.Month > start.Month) ||
        ((end.Month == start.Month) && (end.Day >= start.Day))) ? 1 : 0);
}

Answer 6

Works perfect:

    internal static int GetDifferenceInYears(DateTime startDate)
    {
        int finalResult = 0;

        const int DaysInYear = 365;

        DateTime endDate = DateTime.Now;

        TimeSpan timeSpan = endDate - startDate;

        if (timeSpan.TotalDays > 365)
        {
            finalResult = (int)Math.Round((timeSpan.TotalDays / DaysInYear), MidpointRounding.ToEven);
        }

        return finalResult;
    }