iphone - 如何在 iPhone 上将 NSTimeInterval 分解为年、月、日、小时、分钟和秒？

Question

我有一个跨越数年的时间间隔，我想要从一年到秒的所有时间组件。

我的第一个想法是将时间间隔除以一年中的秒数，从运行总秒数中减去，再除以一个月中的秒数，从运行总数中减去，等等。

这看起来很复杂，而且我读到，每当你做一些看起来很复杂的事情时，可能有一个内置的方法。

在那儿？

我将 Alex 的第二种方法集成到我的代码中。

它在我的界面中由 UIDatePicker 调用的方法中。

NSDate *now = [NSDate date];
NSDate *then = self.datePicker.date;
NSTimeInterval howLong = [now timeIntervalSinceDate:then];

NSDate *date = [NSDate dateWithTimeIntervalSince1970:howLong];
NSString *dateStr = [date description];
const char *dateStrPtr = [dateStr UTF8String];
int year, month, day, hour, minute, sec;

sscanf(dateStrPtr, "%d-%d-%d %d:%d:%d", &year, &month, &day, &hour, &minute, &sec);
year -= 1970;

NSLog(@"%d years\n%d months\n%d days\n%d hours\n%d minutes\n%d seconds", year, month, day, hour, minute, sec);

当我将日期选择器设置为过去 1 年零 1 天的日期时，我得到：

1年1个月1天16小时0分20秒

这是1个月零16小时的休息时间。如果我将日期选择器设置为过去 1 天，我会离开相同的数量。

更新：我有一个应用程序可以计算你的年龄，给定你的生日（从 UIDatePicker 设置），但它经常关闭。这证明有一个不准确的地方，但我无法弄清楚它来自哪里，你能吗？

score 102 · Accepted Answer

Brief Description

Just another approach to complete the answer of JBRWilkinson but adding some code. It can also offers a solution to Alex Reynolds's comment.
Use NSCalendar method:
- (NSDateComponents *)components:(NSUInteger)unitFlags fromDate:(NSDate *)startingDate toDate:(NSDate *)resultDate options:(NSUInteger)opts
- "Returns, as an NSDateComponents object using specified components, the difference between two supplied dates". (From the API documentation).
Create 2 NSDate whose difference is the NSTimeInterval you want to break down. (If your NSTimeInterval comes from comparing 2 NSDate you don't need to do this step, and you don't even need the NSTimeInterval, just apply the dates to the NSCalendar method).
Get your quotes from NSDateComponents

Sample Code

// The time interval 
NSTimeInterval theTimeInterval = ...;

// Get the system calendar
NSCalendar *sysCalendar = [NSCalendar currentCalendar];

// Create the NSDates
NSDate *date1 = [[NSDate alloc] init];
NSDate *date2 = [[NSDate alloc] initWithTimeInterval:theTimeInterval sinceDate:date1]; 

// Get conversion to months, days, hours, minutes
NSCalendarUnit unitFlags = NSHourCalendarUnit | NSMinuteCalendarUnit | NSDayCalendarUnit | NSMonthCalendarUnit;

NSDateComponents *breakdownInfo = [sysCalendar components:unitFlags fromDate:date1  toDate:date2  options:0];
NSLog(@"Break down: %i min : %i hours : %i days : %i months", [breakdownInfo minute], [breakdownInfo hour], [breakdownInfo day], [breakdownInfo month]);

score 17 · Accepted Answer

这段代码知道夏令时和其他可能的讨厌的事情。

NSCalendar *gregorianCalendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components = [gregorianCalendar components: (NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit | NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit )
                                                    fromDate:startDate
                                                      toDate:[NSDate date]
                                                     options:0];


NSLog(@"%ld", [components year]);
NSLog(@"%ld", [components month]);
NSLog(@"%ld", [components day]);
NSLog(@"%ld", [components hour]);
NSLog(@"%ld", [components minute]);
NSLog(@"%ld", [components second]);

score 5 · Accepted Answer

从iOS8及以上你可以使用NSDateComponentsFormatter

它具有在用户友好的格式化字符串中转换时差的方法。

NSDateComponentsFormatter *formatter = [[NSDateComponentsFormatter alloc] init];
formatter.unitsStyle = NSDateComponentsFormatterUnitsStyleFull;

NSLog(@"%@", [formatter stringFromTimeInterval:1623452]);

这给出了输出 - 2 周、4 天、18 小时、57 分钟、32 秒

score 4 · Accepted Answer

将您的时间间隔转换为NSDateusing +dateWithIntervalSince1970，从中获取日期组件 usingNSCalendar的-componentsFromDate方法。

开发工具包参考

score 3 · Accepted Answer

或者有我的课堂方法。它不能处理年，但可以很容易地添加它，尽管它更适合像天、小时和分钟这样的小时间间隔。它考虑了复数，只显示需要的内容：

+(NSString *)TimeRemainingUntilDate:(NSDate *)date {

    NSTimeInterval interval = [date timeIntervalSinceNow];
    NSString * timeRemaining = nil;

    if (interval > 0) {

        div_t d = div(interval, 86400);
        int day = d.quot;
        div_t h = div(d.rem, 3600);
        int hour = h.quot;
        div_t m = div(h.rem, 60);
        int min = m.quot;

        NSString * nbday = nil;
        if(day > 1)
            nbday = @"days";
        else if(day == 1)
            nbday = @"day";
        else
            nbday = @"";
        NSString * nbhour = nil;
        if(hour > 1)
            nbhour = @"hours";
        else if (hour == 1)
            nbhour = @"hour";
        else
            nbhour = @"";
        NSString * nbmin = nil;
        if(min > 1)
            nbmin = @"mins";
        else
            nbmin = @"min";

        timeRemaining = [NSString stringWithFormat:@"%@%@ %@%@ %@%@",day ? [NSNumber numberWithInt:day] : @"",nbday,hour ? [NSNumber numberWithInt:hour] : @"",nbhour,min ? [NSNumber numberWithInt:min] : @"00",nbmin];
    }
    else
        timeRemaining = @"Over";

    return timeRemaining;
}

score 3 · Accepted Answer

这对我有用：

    float *lenghInSeconds = 2345.234513;
    NSDate *date = [NSDate dateWithTimeIntervalSinceReferenceDate:lenghInSeconds];
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];


    [formatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0.0]];

    [formatter setDateFormat:@"HH:mm:ss"];
    NSLog(@"%@", [formatter stringFromDate:date]); 
    [formatter release];

这里的主要区别是您需要调整时区。

score 2 · Accepted Answer

NSDate *date = [NSDate dateWithTimeIntervalSince1970:timeInterval];

// format: YYYY-MM-DD HH:MM:SS ±HHMM
NSString *dateStr = [date description];
NSRange range;

// year
range.location = 0;
range.length = 4;
NSString *yearStr = [dateStr substringWithRange:range];
int year = [yearStr intValue] - 1970;

// month
range.location = 5;
range.length = 2;
NSString *monthStr = [dateStr substringWithRange:range];
int month = [monthStr intValue];

// day, etc.
...

score 0 · Accepted Answer

- (NSString *)convertTimeFromSeconds:(NSString *)seconds {

    // Return variable.
    NSString *result = @"";

    // Int variables for calculation.
    int secs = [seconds intValue];
    int tempHour    = 0;
    int tempMinute  = 0;
    int tempSecond  = 0;

    NSString *hour      = @"";
    NSString *minute    = @"";
    NSString *second    = @"";

    // Convert the seconds to hours, minutes and seconds.
    tempHour    = secs / 3600;
    tempMinute  = secs / 60 - tempHour * 60;
    tempSecond  = secs - (tempHour * 3600 + tempMinute * 60);

    hour    = [[NSNumber numberWithInt:tempHour] stringValue];
    minute  = [[NSNumber numberWithInt:tempMinute] stringValue];
    second  = [[NSNumber numberWithInt:tempSecond] stringValue];

    // Make time look like 00:00:00 and not 0:0:0
    if (tempHour < 10) {
        hour = [@"0" stringByAppendingString:hour];
    } 

    if (tempMinute < 10) {
        minute = [@"0" stringByAppendingString:minute];
    }

    if (tempSecond < 10) {
        second = [@"0" stringByAppendingString:second];
    }

    if (tempHour == 0) {

        NSLog(@"Result of Time Conversion: %@:%@", minute, second);
        result = [NSString stringWithFormat:@"%@:%@", minute, second];

    } else {

        NSLog(@"Result of Time Conversion: %@:%@:%@", hour, minute, second); 
        result = [NSString stringWithFormat:@"%@:%@:%@",hour, minute, second];

    }

    return result;

}

score -2 · Accepted Answer

这是另一种可能性，更简洁：

NSDate *date = [NSDate dateWithTimeIntervalSince1970:timeInterval];
NSString *dateStr = [date description];
const char *dateStrPtr = [dateStr UTF8String];

// format: YYYY-MM-DD HH:MM:SS ±HHMM
int year, month, day, hour, minutes, seconds;
sscanf(dateStrPtr, "%d-%d-%d %d:%d:%d", &year, &month, &day, &hour, &minutes, &seconds);
year -= 1970;

iphone - 如何在 iPhone 上将 NSTimeInterval 分解为年、月、日、小时、分钟和秒？

9 回答 9

Related

Reference