GregorianCalendar Class

Definition

Namespace:

System.Globalization

Assembly:

System.Runtime.dll

Source:

GregorianCalendar.cs

Represents the Gregorian calendar.

public ref class GregorianCalendar : System::Globalization::Calendar

public class GregorianCalendar : System.Globalization.Calendar

type GregorianCalendar = class
    inherit Calendar

Public Class GregorianCalendar
Inherits Calendar

Inheritance

Object

Calendar

GregorianCalendar

Examples

The following code example shows that DateTimeFormatInfo ignores the punctuation in the era name, only if the calendar is Gregorian and the culture uses the era name "A.D.".

using namespace System;
using namespace System::Globalization;
using namespace System::Collections;
int main()
{
   
   // Creates strings with punctuation and without.
   String^ strADPunc = "A.D.";
   String^ strADNoPunc = "AD";
   String^ strCEPunc = "C.E.";
   String^ strCENoPunc = "CE";
   
   // Calls DTFI::GetEra for each culture that uses GregorianCalendar as the default calendar.
   Console::WriteLine( "            ----- AD -----  ----- CE -----" );
   Console::WriteLine( "CULTURE     PUNC   NO PUNC  PUNC   NO PUNC  CALENDAR" );
   IEnumerator^ en = CultureInfo::GetCultures( CultureTypes::SpecificCultures )->GetEnumerator();
   while ( en->MoveNext() )
   {
      CultureInfo^ myCI = safe_cast<CultureInfo^>(en->Current);
      Console::Write( "{0, -12}", myCI );
      Console::Write( "{0,-7}{1,-9}", myCI->DateTimeFormat->GetEra( strADPunc ), myCI->DateTimeFormat->GetEra( strADNoPunc ) );
      Console::Write( "{0, -7}{1, -9}", myCI->DateTimeFormat->GetEra( strCEPunc ), myCI->DateTimeFormat->GetEra( strCENoPunc ) );
      Console::Write( "{0}", myCI->Calendar );
      Console::WriteLine();
   }
}

/*
This code produces the following output.  This output has been cropped for brevity.

            ----- AD -----  ----- CE -----
CULTURE     PUNC   NO PUNC  PUNC   NO PUNC  CALENDAR
ar-SA       -1     -1       -1     -1       System.Globalization.HijriCalendar
ar-IQ       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-EG       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-LY       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-DZ       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-MA       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-TN       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-OM       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-YE       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-SY       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-JO       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-LB       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-KW       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-AE       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-BH       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-QA       1      1        -1     -1       System.Globalization.GregorianCalendar
bg-BG       1      1        -1     -1       System.Globalization.GregorianCalendar
ca-ES       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-TW       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-CN       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-HK       1      1        -1     -1       System.Globalization.GregorianCalendar
zh-SG       1      1        -1     -1       System.Globalization.GregorianCalendar
zh-MO       1      1        -1     -1       System.Globalization.GregorianCalendar
cs-CZ       -1     -1       -1     -1       System.Globalization.GregorianCalendar
da-DK       1      1        -1     -1       System.Globalization.GregorianCalendar

*/

using System;
using System.Globalization;

public class SamplesGregorianCalendar  {

   public static void Main()  {

      // Creates strings with punctuation and without.
      String strADPunc = "A.D.";
      String strADNoPunc = "AD";
      String strCEPunc = "C.E.";
      String strCENoPunc = "CE";

      // Calls DTFI.GetEra for each culture that uses GregorianCalendar as the default calendar.
      Console.WriteLine( "            ----- AD -----  ----- CE -----" );
      Console.WriteLine( "CULTURE     PUNC   NO PUNC  PUNC   NO PUNC  CALENDAR" );
      foreach ( CultureInfo myCI in CultureInfo.GetCultures( CultureTypes.SpecificCultures ) )  {
         Console.Write( "{0,-12}", myCI );
         Console.Write( "{0,-7}{1,-9}", myCI.DateTimeFormat.GetEra( strADPunc ), myCI.DateTimeFormat.GetEra( strADNoPunc ) );
         Console.Write( "{0,-7}{1,-9}", myCI.DateTimeFormat.GetEra( strCEPunc ), myCI.DateTimeFormat.GetEra( strCENoPunc ) );
         Console.Write( "{0}", myCI.Calendar );
         Console.WriteLine();
      }
   }
}

/*
This code produces the following output.  This output has been cropped for brevity.

            ----- AD -----  ----- CE -----
CULTURE     PUNC   NO PUNC  PUNC   NO PUNC  CALENDAR
ar-SA       -1     -1       -1     -1       System.Globalization.HijriCalendar
ar-IQ       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-EG       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-LY       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-DZ       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-MA       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-TN       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-OM       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-YE       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-SY       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-JO       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-LB       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-KW       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-AE       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-BH       1      1        -1     -1       System.Globalization.GregorianCalendar
ar-QA       1      1        -1     -1       System.Globalization.GregorianCalendar
bg-BG       1      1        -1     -1       System.Globalization.GregorianCalendar
ca-ES       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-TW       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-CN       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-HK       -1     -1       -1     -1       System.Globalization.GregorianCalendar
zh-SG       1      1        -1     -1       System.Globalization.GregorianCalendar
zh-MO       1      1        -1     -1       System.Globalization.GregorianCalendar
cs-CZ       -1     -1       -1     -1       System.Globalization.GregorianCalendar
da-DK       1      1        -1     -1       System.Globalization.GregorianCalendar

*/

Imports System.Globalization

Public Class SamplesGregorianCalendar

   Public Shared Sub Main()

      ' Creates strings with punctuation and without.
      Dim strADPunc As [String] = "A.D."
      Dim strADNoPunc As [String] = "AD"
      Dim strCEPunc As [String] = "C.E."
      Dim strCENoPunc As [String] = "CE"

      ' Calls DTFI.GetEra for each culture that uses GregorianCalendar as the default calendar.
      Console.WriteLine("            ----- AD -----  ----- CE -----")
      Console.WriteLine("CULTURE     PUNC   NO PUNC  PUNC   NO PUNC  CALENDAR")
      Dim myCI As CultureInfo
      For Each myCI In  CultureInfo.GetCultures(CultureTypes.SpecificCultures)
         Console.Write("{0,-12}", myCI)
         Console.Write("{0,-7}{1,-9}", myCI.DateTimeFormat.GetEra(strADPunc), myCI.DateTimeFormat.GetEra(strADNoPunc))
         Console.Write("{0,-7}{1,-9}", myCI.DateTimeFormat.GetEra(strCEPunc), myCI.DateTimeFormat.GetEra(strCENoPunc))
         Console.Write("{0}", myCI.Calendar)
         Console.WriteLine()
      Next myCI

   End Sub

End Class


'This code produces the following output.  This output has been cropped for brevity.
'
'            ----- AD -----  ----- CE -----
'CULTURE     PUNC   NO PUNC  PUNC   NO PUNC  CALENDAR
'ar-SA       -1     -1       -1     -1       System.Globalization.HijriCalendar
'ar-IQ       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-EG       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-LY       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-DZ       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-MA       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-TN       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-OM       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-YE       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-SY       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-JO       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-LB       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-KW       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-AE       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-BH       1      1        -1     -1       System.Globalization.GregorianCalendar
'ar-QA       1      1        -1     -1       System.Globalization.GregorianCalendar
'bg-BG       1      1        -1     -1       System.Globalization.GregorianCalendar
'ca-ES       -1     -1       -1     -1       System.Globalization.GregorianCalendar
'zh-TW       -1     -1       -1     -1       System.Globalization.GregorianCalendar
'zh-CN       -1     -1       -1     -1       System.Globalization.GregorianCalendar
'zh-HK       -1     -1       -1     -1       System.Globalization.GregorianCalendar
'zh-SG       1      1        -1     -1       System.Globalization.GregorianCalendar
'zh-MO       1      1        -1     -1       System.Globalization.GregorianCalendar
'cs-CZ       -1     -1       -1     -1       System.Globalization.GregorianCalendar
'da-DK       1      1        -1     -1       System.Globalization.GregorianCalendar

Remarks

The Gregorian calendar recognizes two eras: B.C. or B.C.E., and A.D. or C.E. This implementation of the GregorianCalendar class recognizes only the current era (A.D. or C.E.).

Note

For information about using the GregorianCalendar class and the other calendar classes in the .NET Framework, see Working with Calendars.

A leap year in the Gregorian calendar is defined as a year that is evenly divisible by 4, unless it is divisible by 100. However, years that are divisible by 400 are leap years. For example, the year 1900 was not a leap year, but the year 2000 was. A common year has 365 days and a leap year has 366 days.

The Gregorian calendar has 12 months with 28 to 31 days each: January (31 days), February (28 or 29 days), March (31 days), April (30 days), May (31 days), June (30 days), July (31 days), August (31 days), September (30 days), October (31 days), November (30 days), and December (31 days). February has 29 days during leap years and 28 during common years.

Important

By default, all DateTime and DateTimeOffset values express dates and times in the Gregorian calendar.

The Gregorian calendar was developed as a replacement for the Julian calendar (which is represented by the JulianCalendar class) and was first introduced in a small number of cultures on October 15, 1582. When working with historic dates that precede a culture's adoption of the Gregorian calendar, you should use the original calendar if it is available in the .NET Framework. For example, Denmark changed from the Julian calendar to the Gregorian calendar on February 19 (in the Julian calendar) or March 1 (in the Gregorian calendar) of 1700. In this case, for dates before the adoption of the Gregorian calendar, you should use the Julian calendar. However, note that no culture offers intrinsic support for the JulianCalendar class. You must use the JulianCalendar class as a standalone calendar. For more information, see Working with calendars.

The following example illustrates that February 18, 1700 in the Julian calendar, which is the last day the Julian calendar was officially used in Denmark, is one day earlier than March 1, 1700 in the Gregorian calendar.

using System;
using System.Globalization;
using System.Threading;

public class Example
{
   public static void Main()
   {
      Thread.CurrentThread.CurrentCulture = new CultureInfo("da-DK");

      JulianCalendar jc = new JulianCalendar();
      DateTime lastDate = new DateTime(1700, 2, 18, jc);
      Console.WriteLine("Last date (Gregorian): {0:d}", lastDate);
      Console.WriteLine("Last date (Julian): {0}-{1}-{2}\n", jc.GetDayOfMonth(lastDate),
                        jc.GetMonth(lastDate), jc.GetYear(lastDate));

      DateTime firstDate = lastDate.AddDays(1);
      Console.WriteLine("First date (Gregorian): {0:d}", firstDate);
      Console.WriteLine("First date (Julian): {0}-{1}-{2}",  jc.GetDayOfMonth(firstDate),
                        jc.GetMonth(firstDate), jc.GetYear(firstDate));
   }
}
// The example displays the following output:
//       Last date (Gregorian): 28-02-1700
//       Last date (Julian): 18-2-1700
//
//       First date (Gregorian): 01-03-1700
//       First date (Julian): 19-2-1700

Imports System.Globalization
Imports System.Threading

Module Example
   Public Sub Main()
      Thread.CurrentThread.CurrentCulture = New CultureInfo("da-DK")
      
      Dim jc As New JulianCalendar()
      Dim lastDate As New DateTime(1700, 2, 18, jc)
      Console.WriteLine("Last date (Gregorian): {0:d}", lastDate)
      Console.WriteLine("Last date (Julian): {0}-{1}-{2}", jc.GetDayOfMonth(lastDate),
                        jc.GetMonth(lastDate), jc.GetYear(lastDate))
      Console.WriteLine()
      
      Dim firstDate As DateTime = lastDate.AddDays(1)
      Console.WriteLine("First date (Gregorian): {0:d}", firstDate)
      Console.WriteLine("First date (Julian): {0}-{1}-{2}",  jc.GetDayOfMonth(firstDate),
                        jc.GetMonth(firstDate), jc.GetYear(firstDate))
   End Sub
End Module
' The example displays the following output:
'       Last date (Gregorian): 28-02-1700
'       Last date (Julian): 18-2-1700
'       
'       First date (Gregorian): 01-03-1700
'       First date (Julian): 19-2-1700

Each CultureInfo supports a set of calendars. The Calendar property returns the default calendar for the culture, and the OptionalCalendars property returns an array containing all the calendars supported by the culture. To change the calendar used by a CultureInfo, the application can set the Calendar property to a new Calendar.

GetEra ignores punctuation in abbreviated era names, only if the GregorianCalendar is selected in DateTimeFormatInfo.Calendar and the culture uses "A.D." as the era name, that is, "A.D." is equivalent to "AD".

Constructors

GregorianCalendar()	Initializes a new instance of the GregorianCalendar class using the default GregorianCalendarTypes value.
GregorianCalendar(GregorianCalendarTypes)	Initializes a new instance of the GregorianCalendar class using the specified GregorianCalendarTypes value.

Fields

ADEra	Represents the current era. This field is constant.
CurrentEra	Represents the current era of the current calendar. The value of this field is 0. (Inherited from Calendar)

Properties

AlgorithmType	Gets a value that indicates whether the current calendar is solar-based, lunar-based, or a combination of both.
CalendarType	Gets or sets the GregorianCalendarTypes value that denotes the language version of the current GregorianCalendar.
DaysInYearBeforeMinSupportedYear	Gets the number of days in the year that precedes the year that is specified by the MinSupportedDateTime property. (Inherited from Calendar)
Eras	Gets the list of eras in the GregorianCalendar.
IsReadOnly	Gets a value indicating whether this Calendar object is read-only. (Inherited from Calendar)
MaxSupportedDateTime	Gets the latest date and time supported by the GregorianCalendar type.
MinSupportedDateTime	Gets the earliest date and time supported by the GregorianCalendar type.
TwoDigitYearMax	Gets or sets the last year of a 100-year range that can be represented by a 2-digit year.

Methods

AddDays(DateTime, Int32)	Returns a DateTime that is the specified number of days away from the specified DateTime. (Inherited from Calendar)
AddHours(DateTime, Int32)	Returns a DateTime that is the specified number of hours away from the specified DateTime. (Inherited from Calendar)
AddMilliseconds(DateTime, Double)	Returns a DateTime that is the specified number of milliseconds away from the specified DateTime. (Inherited from Calendar)
AddMinutes(DateTime, Int32)	Returns a DateTime that is the specified number of minutes away from the specified DateTime. (Inherited from Calendar)
AddMonths(DateTime, Int32)	Returns a DateTime that is the specified number of months away from the specified DateTime.
AddSeconds(DateTime, Int32)	Returns a DateTime that is the specified number of seconds away from the specified DateTime. (Inherited from Calendar)
AddWeeks(DateTime, Int32)	Returns a DateTime that is the specified number of weeks away from the specified DateTime. (Inherited from Calendar)
AddYears(DateTime, Int32)	Returns a DateTime that is the specified number of years away from the specified DateTime.
Clone()	Creates a new object that is a copy of the current Calendar object. (Inherited from Calendar)
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetDayOfMonth(DateTime)	Returns the day of the month in the specified DateTime.
GetDayOfWeek(DateTime)	Returns the day of the week in the specified DateTime.
GetDayOfYear(DateTime)	Returns the day of the year in the specified DateTime.
GetDaysInMonth(Int32, Int32, Int32)	Returns the number of days in the specified month in the specified year in the specified era.
GetDaysInMonth(Int32, Int32)	Returns the number of days in the specified month and year of the current era. (Inherited from Calendar)
GetDaysInYear(Int32, Int32)	Returns the number of days in the specified year in the specified era.
GetDaysInYear(Int32)	Returns the number of days in the specified year of the current era. (Inherited from Calendar)
GetEra(DateTime)	Returns the era in the specified DateTime.
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetHour(DateTime)	Returns the hours value in the specified DateTime. (Inherited from Calendar)
GetLeapMonth(Int32, Int32)	Calculates the leap month for a specified year and era.
GetLeapMonth(Int32)	Calculates the leap month for a specified year. (Inherited from Calendar)
GetMilliseconds(DateTime)	Returns the milliseconds value in the specified DateTime. (Inherited from Calendar)
GetMinute(DateTime)	Returns the minutes value in the specified DateTime. (Inherited from Calendar)
GetMonth(DateTime)	Returns the month in the specified DateTime.
GetMonthsInYear(Int32, Int32)	Returns the number of months in the specified year in the specified era.
GetMonthsInYear(Int32)	Returns the number of months in the specified year in the current era. (Inherited from Calendar)
GetSecond(DateTime)	Returns the seconds value in the specified DateTime. (Inherited from Calendar)
GetType()	Gets the Type of the current instance. (Inherited from Object)
GetWeekOfYear(DateTime, CalendarWeekRule, DayOfWeek)	Returns the week of the year that includes the date in the specified DateTime value. (Inherited from Calendar)
GetYear(DateTime)	Returns the year in the specified DateTime.
IsLeapDay(Int32, Int32, Int32, Int32)	Determines whether the specified date in the specified era is a leap day.
IsLeapDay(Int32, Int32, Int32)	Determines whether the specified date in the current era is a leap day. (Inherited from Calendar)
IsLeapMonth(Int32, Int32, Int32)	Determines whether the specified month in the specified year in the specified era is a leap month.
IsLeapMonth(Int32, Int32)	Determines whether the specified month in the specified year in the current era is a leap month. (Inherited from Calendar)
IsLeapYear(Int32, Int32)	Determines whether the specified year in the specified era is a leap year.
IsLeapYear(Int32)	Determines whether the specified year in the current era is a leap year. (Inherited from Calendar)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToDateTime(Int32, Int32, Int32, Int32, Int32, Int32, Int32, Int32)	Returns a DateTime that is set to the specified date and time in the specified era.
ToDateTime(Int32, Int32, Int32, Int32, Int32, Int32, Int32)	Returns a DateTime that is set to the specified date and time in the current era. (Inherited from Calendar)
ToFourDigitYear(Int32)	Converts the specified year to a four-digit year by using the TwoDigitYearMax property to determine the appropriate century.
ToString()	Returns a string that represents the current object. (Inherited from Object)

See also

• Calendar
• Calendar
• OptionalCalendars
• Working with Calendars