Print all era in Japanese Calendar (Japanese/English).

jEras_both.m

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{

    @autoreleasepool {
        NSCalendar *japanese = [[NSCalendar alloc] initWithCalendarIdentifier:NSJapaneseCalendar];
        NSDateFormatter *usFormatter = [[NSDateFormatter alloc] init];
        usFormatter.calendar = japanese;
        usFormatter.locale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US"];
        usFormatter.dateFormat = @"G";
        NSDateFormatter *aFormatter = [[NSDateFormatter alloc] init];
        aFormatter.calendar = japanese;
        aFormatter.locale = [[NSLocale alloc] initWithLocaleIdentifier:@"ja_JP"];
        aFormatter.dateFormat = @"G";

        NSDateComponents *comps = [[NSDateComponents alloc] init];
        comps.year = 1;
        comps.month = 12;
        comps.day = 31;
        for (comps.era = 235; comps.era >= 0; comps.era--) {
            NSDate *aDate = [japanese dateFromComponents:comps];
            printf("%s %s\n",
                   [[aFormatter stringFromDate:aDate] UTF8String],
                   [[usFormatter stringFromDate:aDate] UTF8String]);
        }
    }
    return 0;
}