IOS 노트: 현재 시간을 가져오고 형식 문자열로 변환

현재 시간을 가져오고 일정한 형식 문자열로 전환

- (void)viewDidLoad
{
    [super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
    /* */
    NSDate *data =[NSDate date];
    
    /* data */
    /* NSCalendar */
    NSCalendar *cal = [NSCalendar currentCalendar];
    NSDateComponents *components = [cal components:NSYearCalendarUnit |  
        NSMonthCalendarUnit |
        NSDayCalendarUnit |
        NSHourCalendarUnit |
        NSMinuteCalendarUnit |
        NSSecondCalendarUnit 
        fromDate:data];
    NSLog(@"date/time is %d-%d-%d %02d-%02d-%02d",
          [components year],
          [components month],
          [components day],
          [components hour],
          [components minute],
          [components second]);

    /* NSDateFormatter */
    /*  YYYY-MM-dd  */
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"YYYY-MM-dd"];
    NSString *d1 = [dateFormatter stringFromDate:data];
    NSLog(@"date d1 is %@", d1);

    /*  YYYY MM dd   */
    [dateFormatter setDateFormat:@"YYYY MM dd "];
    NSString *d2 = [dateFormatter stringFromDate:data];
    NSLog(@"date d2 is %@", d2);
}