关于NSDate、NSCalendar

比较两个时间的差值

// 当前时间
NSDate *now = [NSDate date];
NSTimeZone *zone = [NSTimeZone systemTimeZone];
NSInteger interval = [zone secondsFromGMTForDate:now];
NSDate *localeDate = [now  dateByAddingTimeInterval:interval];
NSLog(@"enddate=%@",localeDate);
NSLog(@"other-> \n now->%@", now);
// 另一个时间
NSDate *other = [NSDate dateWithTimeIntervalSinceNow:10000000];
// 日历
NSCalendar *calendar = [NSCalendar currentCalendar];
// 比较时间
NSCalendarUnit unit = NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear | NSCalendarUnitHour |
NSCalendarUnitMinute | NSCalendarUnitSecond;
NSDateComponents *cmps = [calendar components:unit fromDate:other toDate:now options:0];

NSLog(@"other->%@ \n now->%@", other, now);
NSLog(@"%zd %zd %zd %zd %zd %zd", cmps.year, cmps.month, cmps.day, cmps.hour, cmps.minute, cmps.second);

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