Get date of first and last day of week knowing week number

Question

I need to get the date of the first and last day of the week knowing the week number.

I get a start date and an end date, representing the first and last day of a s

Answer 1

Tim Schmelter's method didn't work for Swedish (sv-SE) culture where weeks start on Mondays. This has been tested with en-US and sv-SE.

    public static DateTime GetFirstDateOfWeek(int year, int weekOfYear, CultureInfo cultureInfo)
    {
        DateTime jan1 = new DateTime(year, 1, 1);
        int daysOffset = (int)cultureInfo.DateTimeFormat.FirstDayOfWeek - (int)jan1.DayOfWeek;
        DateTime firstWeekDay = jan1.AddDays(daysOffset);
        int firstWeek = cultureInfo.Calendar.GetWeekOfYear(jan1, cultureInfo.DateTimeFormat.CalendarWeekRule, cultureInfo.DateTimeFormat.FirstDayOfWeek);
        if (firstWeek == 1)
        {
            weekOfYear -= 1;
        }
        return firstWeekDay.AddDays(weekOfYear * 7);
    }