Converting ISO8601 date-times to NSDate and vice-versa

CCJTextEngine.m

#pragma mark - ISO8601 to NSDate & vice-versa

// Convert ISO 8601 standard Zulu date+time to NSDate
+ (NSDate*)convertISO8601ToNSDate:(NSString*)isoString {
    
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.SSSZ"];
    // Always use this locale when parsing fixed format date strings
    NSLocale *posix = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"];
    [formatter setLocale:posix];
    NSDate *date = [formatter dateFromString:isoString];
    
    return date;
}

+ (NSString*)convertNSDateToISO8601String:(NSDate*)nsDate {
    
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    NSLocale *enUSPOSIXLocale = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
    [dateFormatter setLocale:enUSPOSIXLocale];
    [dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ssZZZZZ"];
    
    NSDate *now = [NSDate date];
    NSString *iso8601String = [dateFormatter stringFromDate:now];
    
    return iso8601String;
}