Question

我正在使用NSDate和NSDateFormatter为特定日期创建倒数计时器。唯一的问题是，当我以不同的格式运行代码时，日期会变得混乱。这是原始代码，效果很好。

- (void)updateCountdown {
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"YYYY-MM-dd"];
    NSDate *startingDate = [dateFormatter dateFromString:@"2014-10-08"];
    NSDate *endingDate = [NSDate date];

    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSUInteger unitFlags = NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit|NSHourCalendarUnit|NSMinuteCalendarUnit|NSSecondCalendarUnit;
    NSDateComponents *dateComponents = [calendar components:unitFlags fromDate:startingDate toDate:endingDate options:0];

    NSInteger days     = [dateComponents day];
    NSInteger months   = [dateComponents month];
    NSInteger years    = [dateComponents year];
    NSInteger hours    = [dateComponents hour];
    NSInteger minutes  = [dateComponents minute];
    NSInteger seconds  = [dateComponents second];
    NSString *countdownText = [NSString stringWithFormat:@"%ld Years %ld Months %ld Days %ld Hours %ld Minutes %ld Seconds", (long)days, (long)months, (long)years, (long)hours, (long)minutes, (long)seconds];

    _countdown.text = countdownText;

    [self performSelector:@selector(updateCountdown) withObject:nil afterDelay:1];
}

但是说我想删除这些年，所以我改变了这样的代码：

- (void)updateCountdown {
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"YYYY-MM-dd"];
    NSDate *startingDate = [dateFormatter dateFromString:@"2014-10-08"];
    NSDate *endingDate = [NSDate date];

    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSUInteger unitFlags = NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit|NSHourCalendarUnit|NSMinuteCalendarUnit|NSSecondCalendarUnit;
    NSDateComponents *dateComponents = [calendar components:unitFlags fromDate:startingDate toDate:endingDate options:0];

    NSInteger days     = [dateComponents day];
    NSInteger months   = [dateComponents month];
    NSInteger hours    = [dateComponents hour];
    NSInteger minutes  = [dateComponents minute];
    NSInteger seconds  = [dateComponents second];
    NSString *countdownText = [NSString stringWithFormat:@"%ld Months %ld Days %ld Hours %ld Minutes %ld Seconds", (long)days, (long)months, (long)hours, (long)minutes, (long)seconds];

    _countdown.text = countdownText;

    [self performSelector:@selector(updateCountdown) withObject:nil afterDelay:1];
}

现在突然间，这个数据被整整一个月搞砸了。我该如何解决这个问题？

为什么输出0年-1个月0天-2小时..就像为什么那里有（ - ）？谢谢！

Answer 1

你正在以错误的顺序提出你的论点首先你有

[NSString stringWithFormat:@"%ld Years %ld Months %ld Days %ld Hours %ld Minutes %ld Seconds", (long)days, (long)months, (long)years, (long)hours, (long)minutes, (long)seconds];

您正在进入

几天到一个地方持有人年
和岁月

然后你有

[NSString stringWithFormat:@"%ld Months %ld Days %ld Hours %ld Minutes %ld Seconds", (long)days, (long)months, (long)hours, (long)minutes, (long)seconds];

您正在进入

几天到一个地方持有人
几个月到位只有最后3个看起来像你想要的那样

NSDate输出错误的日期

1 个答案: