PersianCalendar Class

using System;
using System.Globalization;

class Example
{
    public static void Demo(System.Windows.Controls.TextBlock outputBlock) 
    {
        //--------------------------------------------------------------------------------
        // Get today's date.
        //--------------------------------------------------------------------------------
      outputBlock.Text += "\n................. Today ...........................\n";
      PersianCalendar jc = new PersianCalendar();
      DateTime thisDate = DateTime.Now;

        // Display the current date using the Gregorian and Persian calendars.
      outputBlock.Text += "Today is:\n";
      outputBlock.Text += String.Format("   {0:dddd}, {0} in the Gregorian calendar.\n", thisDate);
      outputBlock.Text += String.Format("   {0}, {1}/{2}/{3} {4}:{5}:{6} in the Persian calendar.\n", 
                                        jc.GetDayOfWeek(thisDate), 
                                        jc.GetMonth(thisDate), 
                                        jc.GetDayOfMonth(thisDate), 
                                        jc.GetYear(thisDate), 
                                        jc.GetHour(thisDate), 
                                        jc.GetMinute(thisDate), 
                                        jc.GetSecond(thisDate));
        //--------------------------------------------------------------------------------
        // Fields
        //--------------------------------------------------------------------------------
      outputBlock.Text += "\n............... Fields .............................\n";
      outputBlock.Text += String.Format("PersianEra = {0}\n", PersianCalendar.PersianEra);
        //--------------------------------------------------------------------------------
        // Properties
        //--------------------------------------------------------------------------------
      outputBlock.Text += "\n............... Properties .........................\n";
      outputBlock.Text += "Eras:";
      foreach (int era in jc.Eras)
      {
         outputBlock.Text += String.Format(" era = {0}\n", era);
      }
        //--------------------------------------------------------------------------------
      outputBlock.Text += "\nGregorian Date Range Supported by the Persian Calendar:\n";
      outputBlock.Text += String.Format("   From {0:G}\n", jc.MinSupportedDateTime);
      outputBlock.Text += String.Format("   To {0:G}\n", jc.MaxSupportedDateTime);
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("\nTwoDigitYearMax = {0}\n", jc.TwoDigitYearMax);
        //--------------------------------------------------------------------------------
        // Methods
        //--------------------------------------------------------------------------------
      outputBlock.Text += "\n............ Selected Methods .......................\n";

        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("GetDayOfYear: day = {0}\n", jc.GetDayOfYear(thisDate));
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("GetDaysInMonth: days = {0}\n", 
                                        jc.GetDaysInMonth( thisDate.Year, thisDate.Month, 
                                        PersianCalendar.PersianEra));
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("GetDaysInYear: days = {0}\n", 
                        jc.GetDaysInYear(thisDate.Year, PersianCalendar.PersianEra));
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("GetLeapMonth: leap month (if any) = {0}\n", 
                        jc.GetLeapMonth(thisDate.Year, PersianCalendar.PersianEra));
        //-------------------------------------------------------------
      outputBlock.Text += String.Format("GetMonthsInYear: months in a year = {0}\n", 
                        jc.GetMonthsInYear(thisDate.Year, PersianCalendar.PersianEra));
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("IsLeapDay: This is a leap day = {0}\n", 
                        jc.IsLeapDay(thisDate.Year, thisDate.Month, thisDate.Day, 
                        PersianCalendar.PersianEra));
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("IsLeapMonth: This is a leap month = {0}\n", 
                        jc.IsLeapMonth(thisDate.Year, thisDate.Month, 
                        PersianCalendar.PersianEra));
        //--------------------------------------------------------------------------------
      outputBlock.Text += String.Format("IsLeapYear: 1370 is a leap year = {0}\n", 
                        jc.IsLeapYear(1370, PersianCalendar.PersianEra));
        //--------------------------------------------------------------------------------

        // Get the 4-digit year for a year whose last two digits are 99. The 4-digit year 
        // depends on the current value of the TwoDigitYearMax property.

      outputBlock.Text += "ToFourDigitYear:\n";
      outputBlock.Text += String.Format("  If TwoDigitYearMax = {0}, ToFourDigitYear(99) = {1}\n", 
                         jc.TwoDigitYearMax, jc.ToFourDigitYear(99));
      jc.TwoDigitYearMax = thisDate.Year;
      outputBlock.Text += String.Format("  If TwoDigitYearMax = {0}, ToFourDigitYear(99) = {1}\n", 
                        jc.TwoDigitYearMax, jc.ToFourDigitYear(99));
    }
}
/*
The example produces the following results:

................. Today ...........................

Today is Wednesday, 6/14/2006 11:31:13 AM

............... Fields .............................

PersianEra = 1

............... Properties .........................

Eras: era = 1
MaxSupportedDateTime = 12/31/9999 11:59:59 PM
MinSupportedDateTime = 3/21/0622 12:00:00 AM
TwoDigitYearMax = 1410

................ Methods ...........................

AddMonths: thisDate + 6 months = 12/15/2006 11:31:13 AM
           thisDate - 6 months = 12/15/2005 11:31:13 AM
AddYears:  thisDate + 5 years =  6/14/2011 11:31:13 AM
           thisDate - 3 years =  6/14/2003 11:31:13 AM
GetDayOfMonth: month = 24
GetDayOfWeek: day = Wednesday
GetDayOfYear: day = 86
GetDaysInMonth: days = 31
GetDaysInYear: days = 366
GetEra: era = 1
GetLeapMonth: leap month (if any) = 0
GetMonth: month = 3
GetMonthsInYear: months in a year = 12
GetYear: year = 1385
IsLeapDay: This is a leap day = False
IsLeapMonth: This is a leap month = False
IsLeapYear: 1370 is a leap year = True
ToDateTime:
  Gregorian calendar: 6/10/2006 8:30:15 PM
  Persian calendar:   3/20/1385 8:30:15 PM
ToFourDigitYear:
  If TwoDigitYearMax = 1410, ToFourDigitYear(99) = 1399
  If TwoDigitYearMax = 2006, ToFourDigitYear(99) = 1999

*/