Getting Week Number for the Selected Date in ASP.Net

Question

I am using ASP:Calendar in ASP.NET Website. I need to retrieve DayofWeek whether 1stSunday,2nd Sunday,3rd Sunday or 4th Sunday similarly for other days of that month for the date selected. Kindly help in this. thanks in advance.

Answer 1

You probably already have DateTime variable. If yes, you can use this code to calculate week number:

var currentCulture = CultureInfo.CurrentCulture;
var weekNo = currentCulture.Calendar.GetWeekOfYear(
                new DateTime(2013, 12, 31), //Your date
                currentCulture.DateTimeFormat.CalendarWeekRule,
                currentCulture.DateTimeFormat.FirstDayOfWeek);

Good luck!

Answer 2

Here is example from MSDN:

public class Example
{
   public static void Main()
   {
      DateTimeFormatInfo dfi = DateTimeFormatInfo.CurrentInfo;
      DateTime date1 = new DateTime(2011, 1, 1);
      Calendar cal = dfi.Calendar;

      Console.WriteLine("{0:d}: Week {1} ({2})", date1, 
                        cal.GetWeekOfYear(date1, dfi.CalendarWeekRule, 
                                          dfi.FirstDayOfWeek),
                        cal.ToString().Substring(cal.ToString().LastIndexOf(".") + 1));       
   }
}

And also the link: http://msdn.microsoft.com/en-us/library/system.globalization.calendar.getweekofyear.aspx

Answer 3

I did the following in one of my projects to get current week number in a month

private static int GetWeekNum(DateTime date, CultureInfo culture) 
{ 
  var firstOfMonth = new DateTime(date.Year, date.Month, 1); 
  return GetWeekNumber(date, culture) - GetWeekNumber(firstOfMonth, culture) + 1; 
} 

private static int GetWeekNumber(DateTime date, CultureInfo culture) 
{ 
  return culture.Calendar.GetWeekOfYear(date, 
    culture.DateTimeFormat.CalendarWeekRule, 
    culture.DateTimeFormat.FirstDayOfWeek); 
}