Date and Calendar

Most locales use the standard Gregorian calendar and a set number of date formats. These "default choices" for date formats are available for display by using the EnumDateFormats function. There are other locales which require special considerations when creating a complete list of format choices. Some of these require text strings to be inserted within the date format string, others require a completely different method of computation of the values. These special requirements are addressed by the addition of certain LCTYPE and CALTYPE values. For more information on LCTYPE values, see Locale Information. For more information on CALTYPE values, see Calendar Type Information.

Each locale identifier (LCID) has a default calendar type associated with it. A locale identifier can also have an alternate calendar type. To have an alternate calendar type for an LCID, you must set LOCALE_IOPTIONALCALENDAR to the alternate calendar type for this locale.