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DateTimeFormatInfo.Calendar Property

Definition

Gets or sets the calendar to use for the current culture.

public:
 property System::Globalization::Calendar ^ Calendar { System::Globalization::Calendar ^ get(); void set(System::Globalization::Calendar ^ value); };
public System.Globalization.Calendar Calendar { get; set; }
member this.Calendar : System.Globalization.Calendar with get, set
Public Property Calendar As Calendar

Property Value

The calendar to use for the current culture. The default for InvariantInfo is a GregorianCalendar object.

Exceptions

The property is being set to null.

The property is being set to a Calendar object that is not valid for the current culture.

The property is being set and the DateTimeFormatInfo object is read-only.

Examples

The following example defines a ChangeCalendar method that changes a culture's current calendar to a specified calendar unless it is already the current calendar or if it is not supported by the culture. The code that calls the method instantiates a CultureInfo object that represents the Arabic (Egypt) culture and first attempts to change its calendar to the Japanese calendar. Because the Japanese calendar is not supported, the method makes not change the culture's calendar. However, because the Umm al-Qura calendar is a member of the CultureInfo.OptionalCalendars collection, the method does succeed in making it the current calendar for the ar-EG culture.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      CultureInfo ci = CultureInfo.CreateSpecificCulture("ar-EG");
      Console.WriteLine("The current calendar for the {0} culture is {1}",
                        ci.Name,
                        CalendarUtilities.ShowCalendarName(ci.DateTimeFormat.Calendar));

      CalendarUtilities.ChangeCalendar(ci, new JapaneseCalendar());
      Console.WriteLine("The current calendar for the {0} culture is {1}",
                        ci.Name,
                        CalendarUtilities.ShowCalendarName(ci.DateTimeFormat.Calendar));

      CalendarUtilities.ChangeCalendar(ci, new UmAlQuraCalendar());
      Console.WriteLine("The current calendar for the {0} culture is {1}",
                        ci.Name,
                        CalendarUtilities.ShowCalendarName(ci.DateTimeFormat.Calendar));
   }
}

public class CalendarUtilities
{
   private Calendar newCal;
   private bool isGregorian;

   public static void ChangeCalendar(CultureInfo ci, Calendar cal)
   {
      CalendarUtilities util = new CalendarUtilities(cal);

      // Is the new calendar already the current calendar?
      if (util.CalendarExists(ci.DateTimeFormat.Calendar))
         return;

      // Is the new calendar supported?
      if (Array.Exists(ci.OptionalCalendars, util.CalendarExists))
         ci.DateTimeFormat.Calendar = cal;
   }

   private CalendarUtilities(Calendar cal)
   {
      newCal = cal;

      // Is the new calendar a Gregorian calendar?
      isGregorian = cal.GetType().Name.Contains("Gregorian");
   }

   private bool CalendarExists(Calendar cal)
   {
      if (cal.ToString() == newCal.ToString()) {
         if (isGregorian) {
            if (((GregorianCalendar) cal).CalendarType ==
               ((GregorianCalendar) newCal).CalendarType)
               return true;
         }
         else {
            return true;
         }
      }
      return false;
   }

   public static string ShowCalendarName(Calendar cal)
   {
      string calName = cal.ToString().Replace("System.Globalization.", "");
      if (cal is GregorianCalendar)
         calName += ", Type " + ((GregorianCalendar) cal).CalendarType.ToString();

      return calName;
   }
}
// The example displays the following output:
//    The current calendar for the ar-EG culture is GregorianCalendar, Type Localized
//    The current calendar for the ar-EG culture is GregorianCalendar, Type Localized
//    The current calendar for the ar-EG culture is UmAlQuraCalendar
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim ci As CultureInfo = CultureInfo.CreateSpecificCulture("ar-EG")
      Console.WriteLine("The current calendar for the {0} culture is {1}",
                        ci.Name, 
                        CalendarUtilities.ShowCalendarName(ci.DateTimeFormat.Calendar))

      CalendarUtilities.ChangeCalendar(ci, New JapaneseCalendar())
      Console.WriteLine("The current calendar for the {0} culture is {1}",
                        ci.Name, 
                        CalendarUtilities.ShowCalendarName(ci.DateTimeFormat.Calendar))
      
      CalendarUtilities.ChangeCalendar(ci, New UmAlQuraCalendar())
      Console.WriteLine("The current calendar for the {0} culture is {1}",
                        ci.Name, 
                        CalendarUtilities.ShowCalendarName(ci.DateTimeFormat.Calendar))
   End Sub
End Module

Public Class CalendarUtilities
   Private newCal As Calendar
   Private isGregorian As Boolean
   
   Public Shared Sub ChangeCalendar(ci As CultureInfo, cal As Calendar)
      Dim util As New CalendarUtilities(cal)
      
      ' Is the new calendar already the current calendar?
      If util.CalendarExists(ci.DateTimeFormat.Calendar) Then
         Exit Sub
      End If

      ' Is the new calendar supported?
      If Array.Exists(ci.OptionalCalendars, AddressOf util.CalendarExists) Then
         ci.DateTimeFormat.Calendar = cal
      End If
   End Sub
   
   Private Sub New(cal As Calendar)
      newCal = cal
      
      ' Is the new calendar a Gregorian calendar?
      isGregorian = cal.GetType().Name.Contains("Gregorian")
   End Sub
   
   Private Function CalendarExists(cal As Calendar) As Boolean
      If cal.ToString() = newCal.ToString Then
         If isGregorian Then
            If CType(cal, GregorianCalendar).CalendarType = 
               CType(newCal, GregorianCalendar).CalendarType Then
               Return True
            End If
         Else
            Return True
         End If
      End If
      Return False
   End Function

   Public Shared Function ShowCalendarName(cal As Calendar) As String
      Dim calName As String = cal.ToString().Replace("System.Globalization.", "")
      If TypeOf cal Is GregorianCalendar Then
         calName += ", Type " + CType(cal, GregorianCalendar).CalendarType.ToString()
      End If
      Return calName 
   End Function
End Class
' The example displays the following output:
'    The current calendar for the ar-EG culture is GregorianCalendar, Type Localized
'    The current calendar for the ar-EG culture is GregorianCalendar, Type Localized
'    The current calendar for the ar-EG culture is UmAlQuraCalendar

Remarks

The Calendar property accepts only calendars that are valid for the culture that is associated with the DateTimeFormatInfo object. The CultureInfo.OptionalCalendars property specifies the calendars that can be used by a particular culture, and the CultureInfo.Calendar property specifies the default calendar for the culture.

Important

Eras in the Japanese calendars are based on the emperor's reign and are therefore expected to change. For example, May 1, 2019 marked the beginning of the Reiwa era in the JapaneseCalendar and JapaneseLunisolarCalendar. Such a change of era affects all applications that use these calendars. For more information and to determine whether your applications are affected, see Handling a new era in the Japanese calendar in .NET. For information on testing your applications on Windows systems to ensure their readiness for the era change, see Prepare your application for the Japanese era change. For features in .NET that support calendars with multiple eras and for best practices when working with calendars that support multiple eras, see Working with eras.

Changing the value of this property affects the following properties as well: MonthNames, AbbreviatedMonthNames, DayNames, AbbreviatedDayNames, CalendarWeekRule, FirstDayOfWeek, FullDateTimePattern, LongDatePattern, ShortDatePattern, YearMonthPattern, and MonthDayPattern.

For example, if the culture of the current thread is Japanese, this property accepts JapaneseCalendar, LocalizedGregorianCalendar, or USEnglishGregorianCalendar. When the JapaneseCalendar is used, the default long date specifier is "gg y'\x5e74'M'\x6708'd'\x65e5'". When the LocalizedGregorianCalendar, is used, the default long date specifier is "yyyy'\x5e74'M'\x6708'd'\x65e5'".

Applies to

See also