The C# method uses the DateTime object to get the week number of a given date. The number returned is dependent on the culture of the target machine.

1. public static int GetWeekNumber(DateTime dtPassed)
2. {
3.         CultureInfo ciCurr = CultureInfo.CurrentCulture;
4.         int weekNum = ciCurr.Calendar.GetWeekOfYear(dtPassed,  CalendarWeekRule.FirstFourDayWeek, DayOfWeek.Monday);
5.         return weekNum;
6. }