NSDate、NSCalendar 和 NSDateComponents 计时

Question

NSDate *today = [NSDate date];
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
[calendar setTimeZone:[NSTimeZone timeZoneWithName:@"GMT+2"]];

NSDateComponents *dateComponents = [calendar components:(NSDayCalendarUnit | NSWeekdayCalendarUnit) fromDate:today];    

NSInteger day = [dateComponents day];
NSInteger month = [dateComponents month];
NSInteger year = [dateComponents year];

 NSLog(@" %i %i %i ", day, month, year);

该代码显示“12 2147483647 2147483647”

如何获取月份和年份（整数）

如何添加/转发一天？ （如果我们也是这个月的第一天！）

感谢您的关注:-)

Answer 1

NSCalendar *calendar= [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSCalendarUnit unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit |  NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
NSDate *date = [NSDate date];
NSDateComponents *dateComponents = [calendar components:unitFlags fromDate:date];

NSInteger year = [dateComponents year];
NSInteger month = [dateComponents month];
NSInteger day = [dateComponents day];
NSInteger hour = [dateComponents hour];
NSInteger minute = [dateComponents minute];
NSInteger second = [dateComponents second];

[calendar release];

希望这有帮助

Answer 2

1. 向 NSDayCalendarUnit | 添加更多单位NSWeekdayCalendarUnit - 您没有请求月份或年份，因此它们无效！

2. 添加/减去配置为 1 天的 NSDateComponents 对象和 [NSCalendar dateByAddingComponents:toDate:options:]。或者，也可能同样正确，使用 [NSDate dateWithTimeInterval:sinceDate:]