1、NSDate

时间与日期的初始化,主要有

[NSDate date];

 

2、NSDateFormatter

 

//NSDate转NSStringstringFromDate:dt//NSString转NSDatedateFromString

 

 

 

 

 

 

3、NSCalendar和NSDateComponents

 

 

4、NSTimer

+ (NSTimer *)timerWithTimeInterval:(NSTimeInterval)ti invocation:(NSInvocation *)invocation repeats:(BOOL)yesOrNo;
+ (NSTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)ti invocation:(NSInvocation *)invocation repeats:(BOOL)yesOrNo;+ (NSTimer *)timerWithTimeInterval:(NSTimeInterval)ti target:(id)aTarget selector:(SEL)aSelector userInfo:(nullable id)userInfo repeats:(BOOL)yesOrNo;
+ (NSTimer *)scheduledTimerWithTimeInterval:(NSTimeInterval)ti target:(id)aTarget selector:(SEL)aSelector userInfo:(nullable id)userInfo repeats:(BOOL)yesOrNo;

 

 

 

5、测试Demo

main.m文件

int main(int argc, char * argv[]) {@autoreleasepool {//NSDate常用方法NSDate *date = [NSDate date];NSLog(@"%@", date);NSDate *date1 = [[NSDate alloc] initWithTimeIntervalSinceNow:3600 * 24];NSLog(@"date1 is %@", date1);NSDate *date2 = [[NSDate alloc] initWithTimeIntervalSinceNow:-3 * 3600 * 24];NSLog(@"date1 is %@", date2);NSLocale *cn = [NSLocale currentLocale];NSLog(@"%@", [date1 descriptionWithLocale:cn]);NSLog(@"%@", [date1 earlierDate:date2]);//NSDate转NSStringNSDate *dt = [NSDate dateWithTimeIntervalSince1970:3600 * 24 * 366 * 20];NSDate *dt1 = [NSDate dateWithTimeIntervalSince1970:0];NSLog(@"%@", dt1);NSDateFormatter *df = [[NSDateFormatter alloc] init];[df setDateFormat:@"公元yyyy年MM月DD日 HH时mm分"];NSLog(@"%@", [df stringFromDate:dt]);//NSString转NSDateNSString *str = @"2018-03-02";NSDateFormatter *df1 = [[NSDateFormatter alloc] init];[df1 setDateFormat:@"yyyy-MM-dd"];NSLog(@"%@", [df1 dateFromString:str]);//NSCalendar和NSDateComponents使用NSCalendar *car = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];NSDate *date3 = [NSDate date];unsigned unit = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit | NSWeekdayCalendarUnit;NSDateComponents *comp = [car components:unit fromDate:date3];NSLog(@"现在是%ld年", comp.year);NSLog(@"现在是%ld月", comp.month);NSLog(@"现在是%ld日", comp.day);NSLog(@"现在是%ld时", comp.hour);NSLog(@"现在是%ld分", comp.minute);NSLog(@"现在是%ld秒", comp.second);NSLog(@"现在是星期%ld", comp.weekday);NSDateComponents *comp1 = [[NSDateComponents alloc] init];comp1.year = 2015;comp1.month = 4;comp1.day = 5;comp1.hour = 18;comp1.minute = 34;NSDate *date4 = [car dateFromComponents:comp1];NSLog(@"date is %@:", date4);return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));}
}

 

 

 

 

 

ViewControl.m文件(这里实现的定时器)

@implementation ViewController- (void)viewDidLoad {[super viewDidLoad];
//    Control *control = [Control new];
//    control.delegate = self;
//    [control willShowAlert];NSTimer* timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(Timered:) userInfo:nil repeats:YES];
}- (void)Timered:(NSTimer*)timer {NSLog(@"hello chenyu");
}
@end

 

 

 

 

 

6、运行的结果

2018-07-12 23:03:31.634870+0800 cyTest[37918:6787840] hello chenyu
2018-07-12 23:03:32.634915+0800 cyTest[37918:6787840] hello chenyu
2018-07-12 23:03:33.634881+0800 cyTest[37918:6787840] hello chenyu
2018-07-12 23:03:34.634938+0800 cyTest[37918:6787840] hello chenyu
2018-07-12 23:03:35.634998+0800 cyTest[37918:6787840] hello chenyu
2018-07-12 23:03:36.635095+0800 cyTest[37918:6787840] hello chenyu
2018-07-12 23:03:37.635086+0800 cyTest[37918:6787840] hello chenyu2018-07-12 23:14:23.789640+0800 cyTest[38218:6796894] Thu Jul 12 23:14:23 2018
2018-07-12 23:14:23.790844+0800 cyTest[38218:6796894] date1 is Fri Jul 13 23:14:23 2018
2018-07-12 23:14:23.791492+0800 cyTest[38218:6796894] date1 is Mon Jul  9 23:14:23 2018
2018-07-12 23:14:23.804598+0800 cyTest[38218:6796894] Friday, July 13, 2018 at 11:14:23 PM China Standard Time
2018-07-12 23:14:23.804853+0800 cyTest[38218:6796894] Mon Jul  9 23:14:23 2018
2018-07-12 23:14:23.805346+0800 cyTest[38218:6796894] Thu Jan  1 08:00:00 1970
2018-07-12 23:14:23.805927+0800 cyTest[38218:6796894] 公元1990年01月16日 08时00分
2018-07-12 23:14:23.808330+0800 cyTest[38218:6796894] Fri Mar  2 00:00:00 2018
2018-07-12 23:14:23.808982+0800 cyTest[38218:6796894] 现在是2018年
2018-07-12 23:14:23.809150+0800 cyTest[38218:6796894] 现在是7月
2018-07-12 23:14:23.809354+0800 cyTest[38218:6796894] 现在是12日
2018-07-12 23:14:23.809558+0800 cyTest[38218:6796894] 现在是23时
2018-07-12 23:14:23.809684+0800 cyTest[38218:6796894] 现在是14分
2018-07-12 23:14:23.809834+0800 cyTest[38218:6796894] 现在是23秒
2018-07-12 23:14:23.810407+0800 cyTest[38218:6796894] 现在是星期5
2018-07-12 23:14:23.811211+0800 cyTest[38218:6796894] date is Sun Apr  5 18:34:00 2015:
2018-07-12 23:14:27.764633+0800 cyTest[38218:6796894] hello chenyu
2018-07-12 23:14:28.764758+0800 cyTest[38218:6796894] hello chenyu
2018-07-12 23:14:29.765776+0800 cyTest[38218:6796894] hello chenyu
2018-07-12 23:14:30.765792+0800 cyTest[38218:6796894] hello chenyu
2018-07-12 23:14:31.765426+0800 cyTest[38218:6796894] hello chenyu