Question

I have DateTime value and I want to determine is this date on:

• Current week
• Current month
• Current year

How can I do this?

Answer 1

You can use the Calendar class of the .NET framework.

public static bool IsCurrentWeek(this DateTime dt)
{
    var f = DateTimeFormatInfo.CurrentInfo;
    var c = f.Calendar;
    var givenWeek = c.GetWeekOfYear(dt, f.CalendarWeekRule, f.FirstDayOfWeek);
    var givenYear = c.GetYear(dt);
    var thisWeek = c.GetWeekOfYear(DateTime.Now, f.CalendarWeekRule, f.FirstDayOfWeek);
    var thisYear = c.GetYear(DateTime.Now);
    return thisWeek == givenWeek && thisYear == givenYear;
}

public static bool IsCurrentMonth(this DateTime dt)
{
    return DateTime.Now.Month == dt.Month && dt.IsCurrentYear();
}

public static bool IsCurrentYear(this DateTime dt)
{
    return DateTime.Now.Year == dt.Year;
}

DateTime dateTime = DateTime.Now;
bool isCurrentYear = dateTime.IsCurrentYear()