System.Globalization Namespace

---

Represents the Japanese calendar.

JapaneseCalendar Class Members

Show Inherited Members

Constructors Visibility Constructor Parameters public JapaneseCalendar ( )   Properties Visibility Name Value Type Accessibility public AlgorithmType CalendarAlgorithmType [ Get ] public Eras Int32 [ Get ] public MaxSupportedDateTime DateTime [ Get ] public MinSupportedDateTime DateTime [ Get ] public TwoDigitYearMax Int32 [ Get , Set ]   Methods Visibility Name Parameters Return Type public AddMonths ( DateTime time , Int32 months ) DateTime public AddYears ( DateTime time , Int32 years ) DateTime public GetDayOfMonth ( DateTime time ) Int32 public GetDayOfWeek ( DateTime time ) DayOfWeek public GetDayOfYear ( DateTime time ) Int32 public GetDaysInMonth ( Int32 year , Int32 month , Int32 era ) Int32 public GetDaysInYear ( Int32 year , Int32 era ) Int32 public GetEra ( DateTime time ) Int32 public GetLeapMonth ( Int32 year , Int32 era ) Int32 public GetMonth ( DateTime time ) Int32 public GetMonthsInYear ( Int32 year , Int32 era ) Int32 public GetWeekOfYear ( DateTime time , CalendarWeekRule rule , DayOfWeek firstDayOfWeek ) Int32 public GetYear ( DateTime time ) Int32 public IsLeapDay ( Int32 year , Int32 month , Int32 day , Int32 era ) Boolean public IsLeapMonth ( Int32 year , Int32 month , Int32 era ) Boolean public IsLeapYear ( Int32 year , Int32 era ) Boolean public ToDateTime ( Int32 year , Int32 month , Int32 day , Int32 hour , Int32 minute , Int32 second , Int32 millisecond , Int32 era ) DateTime public ToFourDigitYear ( Int32 year ) Int32

The Japanese calendar, which is also known as the Wareki calendar, works exactly like the Gregorian calendar, except that the year and era are different.

The Japanese calendar recognizes one era for every emperor's reign. The current era is the Heisei era, which began in the Gregorian calendar year 1989. The era name is typically displayed before the year. For example, the Gregorian calendar year 2001 is the Japanese calendar year Heisei 13. Note that the first year of an era is called "Gannen"; therefore, the Gregorian calendar year 1989 was the Japanese calendar year Heisei Gannen.

This class assigns numbers to the eras as follows:

GetEra value	Era Name	Era Abbreviation	Gregorian Dates
4	平成 ( Heisei )	平 ( H, h )	January 8, 1989 to present
3	昭和 ( Showa )	昭 ( S, s )	December 25, 1926 to January 7, 1989
2	大正 ( Taisho )	大 ( T, t )	July 30, 1912 to December 24, 1926
1	明治 ( Meiji )	明 ( M, m )	September 8, 1868 to July 29, 1912

This class only handles dates from the eighth day of the ninth month in the year Meiji 3 ( September 8, 1868 of the Gregorian calendar ). Although the Japanese calendar was switched from a lunar calendar to a solar calendar in the year Meiji 6 ( 1873 of the Gregorian calendar ), this implementation is based on the solar calendar only.

Leap years in the Japanese calendar correspond to the same leap years in the Gregorian calendar. A leap year in the Gregorian calendar is defined as a Gregorian year that is evenly divisible by four, except if it is divisible by 100; however, Gregorian years that are divisible by 400 are leap years. A common year has 365 days and a leap year has 366 days.

The Japanese calendar has 12 months with 28 to 31 days each:

GetMonth value	Month	English	Days in common years	Days in leap years
1	1月 ( Ichigatsu )	January	31	31
2	2月 ( Nigatsu )	February	28	29
3	3月 ( Sangatsu )	March	31	31
4	4月 ( Shigatsu )	April	30	30
5	5月 ( Gogatsu )	May	31	31
6	6月 ( Rokugatsu )	June	30	30
7	7月 ( Shichigatsu )	July	31	31
8	8月 ( Hachigatsu )	August	31	31
9	9月 ( Kugatsu )	September	30	30
10	10月 ( Juugatsu )	October	31	31
11	11月 ( Juuichigatsu )	November	30	30
12	12月 ( Juunigatsu )	December	31	31

Nigatsu, which is equivalent to the Gregorian calendar month of February, has 29 days during leap years and 28 during common years.

The date January 1, 2001 A.D. in the Gregorian calendar is equivalent to the first day of Ichigatsu in the year Heisei 13 in the Japanese calendar.

If using the JapaneseCalendar class, DateTime.Parse will recognize the era abbreviations in front of the year; that is, either the single-character case-insensitive Latin alphabet abbreviation or the single-character Kanji abbreviation.

Calendar   GregorianCalendar

Suggested Reading