NSCalendar calendarIdentifier example in Objective C (iOS).

NSCalendar calendarIdentifier

Returns the identifier for the receiver.

- (NSString *)calendarIdentifier

Return Value of [NSCalendar calendarIdentifier]
The identifier for the receiver. For valid identifiers, see NSLocale.

NSCalendar calendarIdentifier example.

NSCalendar *calendarIdentifier = [[NSCalendar currentCalendar] calendarIdentifier];
NSCalendar *calendar = [[[NSCalendar alloc] initWithCalendarIdentifier:calendarIdentifier] autorelease];
[calendar setFirstWeekday:2];

Example of [NSCalendar calendarIdentifier].

- (NSInteger)daysApartFrom:(NSDate *)startDate toDate:(NSDate *)endDate usingCalendar:(NSCalendar *)localizedTZCal {

    static NSTimeZone *timeZoneUtc;
    static NSCalendar *utcCal;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        timeZoneUtc = [NSTimeZone timeZoneWithName:@"UTC"];

        utcCal = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];       
        utcCal.timeZone = timeZoneUtc;
    });

    NSInteger componentFlags = NSEraCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit;
    NSDateComponents *componentsStartDate = [localizedTZCal components:componentFlags fromDate:startDate];
    NSDateComponents *componentsEndDate = [localizedTZCal components:componentFlags fromDate:endDate];

    NSDate *utcStartDate = [utcCal dateFromComponents:componentsStartDate];
    NSDate *utcEndDate = [utcCal dateFromComponents:componentsEndDate];

    NSInteger utcDaysDiff = [self daysWithinEraFromDate:utcStartDate toDate:utcEndDate usingCalendar:utcCal];
    return utcDaysDiff;
}

NSCalendar calendarIdentifier example.

[self convertGregorianYearToLocaleYear:NSRepublicOfChinaCalendar withYear:1995];
// 84
[self convertGregorianYearToLocaleYear:NSRepublicOfChinaCalendar withYear:2011];
// 100

NSCalendar *calendar = [NSCalendar currentCalendar];
[self convertGregorianYearToLocaleYear:[calendar calendarIdentifier] withYear:2010];

End of NSCalendar calendarIdentifier example article.