PersianCalendar Class
Assembly: mscorlib (in mscorlib.dll)
The Persian calendar is used in most countries where Persian is spoken, although some regions use different month names. The Persian calendar is the official calendar of Iran and Afghanistan, and is one of the alternative calendars in regions such as Kazakhstan and Tajikistan.
Dates in the Persian calendar start from the year of the Hijra, which corresponds to 622 C.E. and is the year when Muhammad migrated from Mecca to Medina. For example, the date March 21, 2002 C.E. corresponds to the first day of the month of Farvardeen in the year 1381 Anno Persico.
The Persian calendar is based on a solar year and is approximately 365 days long. A year cycles through four seasons, and a new year begins when the sun appears to cross the equator from the southern hemisphere to the northern hemisphere as viewed from the center of the Earth. The new year marks the first day of the month of Farvardeen, which is the first day of spring in the northern hemisphere.
Each of the first six months in the Persian calendar has 31 days, each of the next five months has 30 days, and the last month has 29 days in a common year and 30 days in a leap year. A leap year is a year that, when divided by 33, has a remainder of 1, 5, 9, 13, 17, 22, 26, or 30. For example, the year 1370 is a leap year because dividing it by 33 yields a remainder of 17. There are approximately 8 leap years in every 33-year cycle.
Using the PersianCalendar
Use a PersianCalendar object to calculate dates in the Persian calendar, or to convert Persian dates to and from Gregorian dates.
Do not use a PersianCalendar object as the default calendar for a culture. The default calendar is specified by the CultureInfo.Calendar property, and must be one of the calendars returned by the CultureInfo.OptionalCalendars property. Currently, the PersianCalendar class is not an optional calendar for any culture supported by the CultureInfo class and consequently cannot be a default calendar.
The following code example demonstrates the field, property, and method members of the PersianCalendar class.
' This example demonstrates the members of the PersianCalendar class. Imports System Imports System.Globalization Class Sample Public Shared Sub Main() '-------------------------------------------------------------------------------- ' Get today's date. '-------------------------------------------------------------------------------- Console.WriteLine(vbCrLf & _ "................. Today ..........................." & vbCrLf) Dim jc As New PersianCalendar() Dim thisDate As DateTime = DateTime.Now ' Use thisDate twice to display the name of the day and the current date. Console.WriteLine("Today is {0:dddd}, {0}", thisDate) '-------------------------------------------------------------------------------- ' Fields '-------------------------------------------------------------------------------- Console.WriteLine(vbCrLf & _ "............... Fields ............................" & vbCrLf) Console.WriteLine("PersianEra = {0}", PersianCalendar.PersianEra) '-------------------------------------------------------------------------------- ' Properties '-------------------------------------------------------------------------------- Console.WriteLine(vbCrLf & _ "............... Properties ........................." & vbCrLf) Console.Write("Eras:") Dim era As Integer For Each era In jc.Eras Console.WriteLine(" era = {0}", era) Next era '-------------------------------------------------------------------------------- Console.WriteLine("MaxSupportedDateTime = {0:G}", jc.MaxSupportedDateTime) '-------------------------------------------------------------------------------- Console.WriteLine("MinSupportedDateTime = {0:G}", jc.MinSupportedDateTime) '-------------------------------------------------------------------------------- Console.WriteLine("TwoDigitYearMax = {0}", jc.TwoDigitYearMax) '-------------------------------------------------------------------------------- ' Methods '-------------------------------------------------------------------------------- Console.WriteLine(vbCrLf & _ "................ Methods ..........................." & vbCrLf) ' Create a date six months in the future and another date six months in the past. Dim plus6Months As DateTime = jc.AddMonths(thisDate, 6) Dim minus6Months As DateTime = jc.AddMonths(thisDate, -6) Console.WriteLine("AddMonths: thisDate + 6 months = {0}", plus6Months) Console.WriteLine(" thisDate - 6 months = {0}", minus6Months) '-------------------------------------------------------------------------------- ' Create a date five years in the future and another date three years in the past. Dim plus5Years As DateTime = jc.AddYears(thisDate, 5) Dim minus3Years As DateTime = jc.AddYears(thisDate, -3) Console.WriteLine("AddYears: thisDate + 5 years = {0}", plus5Years) Console.WriteLine(" thisDate - 3 years = {0}", minus3Years) '-------------------------------------------------------------------------------- Console.WriteLine("GetDayOfMonth: month = {0}", jc.GetDayOfMonth(thisDate)) '-------------------------------------------------------------------------------- Console.WriteLine("GetDayOfWeek: day = {0}", jc.GetDayOfWeek(thisDate)) '-------------------------------------------------------------------------------- Console.WriteLine("GetDayOfYear: day = {0}", jc.GetDayOfYear(thisDate)) '-------------------------------------------------------------------------------- Console.WriteLine("GetDaysInMonth: days = {0}", _ jc.GetDaysInMonth(thisDate.Year, _ thisDate.Month, _ PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- Console.WriteLine("GetDaysInYear: days = {0}", _ jc.GetDaysInYear(thisDate.Year, PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- Console.WriteLine("GetEra: era = {0}", jc.GetEra(thisDate)) '-------------------------------------------------------------------------------- Console.WriteLine("GetLeapMonth: leap month (if any) = {0}", _ jc.GetLeapMonth(thisDate.Year, PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- Console.WriteLine("GetMonth: month = {0}", jc.GetMonth(thisDate)) '-------------------------------------------------------------------------------- Console.WriteLine("GetMonthsInYear: months in a year = {0}", _ jc.GetMonthsInYear(thisDate.Year, PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- Console.WriteLine("GetYear: year = {0}", jc.GetYear(thisDate)) '-------------------------------------------------------------------------------- Console.WriteLine("IsLeapDay: This is a leap day = {0}", _ jc.IsLeapDay(thisDate.Year, _ thisDate.Month, thisDate.Day, _ PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- Console.WriteLine("IsLeapMonth: This is a leap month = {0}", _ jc.IsLeapMonth(thisDate.Year, _ thisDate.Month, _ PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- Console.WriteLine("IsLeapYear: 1370 is a leap year = {0}", _ jc.IsLeapYear(1370, PersianCalendar.PersianEra)) '-------------------------------------------------------------------------------- ' Create a date in the Gregorian calendar and the Persian calendar. The date is ' the current date and an arbitrary time of 20 hours, 30 minutes, and 15.5 ' seconds. Dim dt1 As New DateTime(thisDate.Year, thisDate.Month, thisDate.Day, _ 20, 30, 15, 500) Dim dt2 As DateTime = jc.ToDateTime(thisDate.Year, thisDate.Month, _ thisDate.Day, _ 20, 30, 15, 500, _ PersianCalendar.PersianEra) Console.WriteLine("ToDateTime:") Console.WriteLine(" Gregorian calendar: {0}", dt1) Console.WriteLine(" Persian calendar: {0}", dt2) '-------------------------------------------------------------------------------- ' 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. Console.WriteLine("ToFourDigitYear:") Console.WriteLine(" If TwoDigitYearMax = {0}, ToFourDigitYear(99) = {1}", _ jc.TwoDigitYearMax, jc.ToFourDigitYear(99)) jc.TwoDigitYearMax = thisDate.Year Console.WriteLine(" If TwoDigitYearMax = {0}, ToFourDigitYear(99) = {1}", _ jc.TwoDigitYearMax, jc.ToFourDigitYear(99)) End Sub 'Main End Class 'Sample ' 'This code example produces the following results: ' '................. Today ........................... ' 'Today is Friday, 8/20/2004 1:08:37 PM ' '............... 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 = 2/18/2005 1:08:37 PM ' thisDate - 6 months = 2/19/2004 1:08:37 PM 'AddYears: thisDate + 5 years = 8/21/2009 1:08:37 PM ' thisDate - 3 years = 8/21/2001 1:08:37 PM 'GetDayOfMonth: month = 30 'GetDayOfWeek: day = Friday 'GetDayOfYear: day = 154 'GetDaysInMonth: days = 30 'GetDaysInYear: days = 365 'GetEra: era = 1 'GetLeapMonth: leap month (if any) = 0 'GetMonth: month = 5 'GetMonthsInYear: months in a year = 12 'GetYear: year = 1383 'IsLeapDay: This is a leap day = False 'IsLeapMonth: This is a leap month = False 'IsLeapYear: 1370 is a leap year = True 'ToDateTime: ' Gregorian calendar: 8/20/2004 8:30:15 PM ' Persian calendar: 11/11/2625 8:30:15 PM 'ToFourDigitYear: ' If TwoDigitYearMax = 1410, ToFourDigitYear(99) = 1399 ' If TwoDigitYearMax = 2004, ToFourDigitYear(99) = 1999 '
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.