如果我的NSTimeInterval设置为200.0，是否有办法将其转换为00:03:20，我想我可以用它初始化NSDate，然后使用HH：mm：ss使用NSDateFormatter。我的问题是，有没有一种快速的方法来执行此操作，或者我必须自己分解并使用数字[NSString stringWithFormat: %02d:%02d:%02d, myHour, myMin, mySec]？

无需使用NSDateFormatter除除法和取模以外的任何方法。NSTimeInterval仅是包含秒数的两倍。

迅速

func stringFromTimeInterval(interval: NSTimeInterval) -> String {
    let interval = Int(interval)
    let seconds = interval % 60
    let minutes = (interval / 60) % 60
    let hours = (interval / 3600)
    return String(format: "%02d:%02d:%02d", hours, minutes, seconds)
}

物镜

- (NSString *)stringFromTimeInterval:(NSTimeInterval)interval {
    NSInteger ti = (NSInteger)interval;
    NSInteger seconds = ti % 60;
    NSInteger minutes = (ti / 60) % 60;
    NSInteger hours = (ti / 3600);
    return [NSString stringWithFormat:@"%02ld:%02ld:%02ld", (long)hours, (long)minutes, (long)seconds];
}

在iOS 8上，使用NSDateComponentsFormatter。

NSDateComponentsFormatter *dateComponentsFormatter = [[NSDateComponentsFormatter alloc] init];
NSLog(@"%@", [dateComponentsFormatter stringFromTimeInterval:200.0]);

输出“ 3:20”。

NSDateComponentsFormatter *dateComponentsFormatter = [[NSDateComponentsFormatter alloc] init];
dateComponentsFormatter.zeroFormattingBehavior = NSDateComponentsFormatterZeroFormattingBehaviorPad;
dateComponentsFormatter.allowedUnits = (NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond);
NSLog(@"%@", [dateComponentsFormatter stringFromTimeInterval:200.0]);

输出“ 0:03:20”。

Swift 3版本的onmyway133的答案：

import Foundation

func format(_ duration: TimeInterval) -> String {
    let formatter = DateComponentsFormatter()
    formatter.zeroFormattingBehavior = .pad
    formatter.allowedUnits = [.minute, .second]

    if duration >= 3600 {
        formatter.allowedUnits.insert(.hour)
    }

    return formatter.string(from: duration)!
}


print(format(12)) // 0:12
print(format(65)) // 1:05
print(format(1750)) // 29:10
print(format(3890)) // 1:04:50
print(format(45720)) // 12:42:00

一些额外的代码行，但是我觉得使用NSDateComponents将提供更精确的值。

- (NSString *)getTimeRepresentationFromDate:(NSDate *)iDate withTimeInterval:(NSTimeInterval)iTimeInterval {
    NSString *aReturnValue = nil;
    NSDate *aNewDate = [iDate dateByAddingTimeInterval:iTimeInterval]; 

    unsigned int theUnits = NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
    NSCalendar *aCalender = [NSCalendar currentCalendar];
    NSDateComponents *aDateComponents = [aCalender components:theUnits fromDate:iDate toDate:aNewDate options:0];

    aReturnValue = [NSString stringWithFormat:@"%d:%d:%d", [aDateComponents hour], [aDateComponents minute], [aDateComponents second]];

    return aReturnValue;
}

在Swift 2中，iOS 8+。这样可以确保我们仅在必要时显示小时

func format(duration: NSTimeInterval) -> String {
  let formatter = NSDateComponentsFormatter()
  formatter.zeroFormattingBehavior = .Pad

  if duration >= 3600 {
    formatter.allowedUnits = [.Hour, .Minute, .Second]
  } else {
    formatter.allowedUnits = [.Minute, .Second]
  }

  return formatter.stringFromTimeInterval(duration) ?? ""
}

所以你有了

print(format(12)) // 0:12
print(format(65)) // 1:05
print(format(1750)) // 29:10
print(format(3890)) // 1:04:50
print(format(45720)) // 12:42:00

NSTimeInterval ti = 3667;
double hours = floor(ti / 60 / 60);
double minutes = floor((ti - (hours * 60 * 60)) / 60);
double seconds = floor(ti - (hours * 60 * 60) - (minutes * 60));

斯威夫特4

DateComponentsFormatter().string(from: <# TimeInterval #>)

例如：

DateComponentsFormatter().string(from: 59.0)

为了“扩展” Matthias Bauch的建议，在Swift中，我将其设为NSTimeInterval的计算属性：

extension NSTimeInterval {
  var stringValue: String {
    let interval = Int(self)
    let seconds = interval % 60
    let minutes = (interval / 60) % 60
    let hours = (interval / 3600)
    return String(format: "%02d:%02d:%02d", hours, minutes, seconds)
  }
}

这样做的好处是它附加在NSTimeInterval类型上，而不是视图控制器或附加在该函数上的任何其他位置。要使用它，您需要执行以下操作：

let timeInterval = NSDate().timeIntervalSinceDate(start)        
self.elapsedTimeLabel.text = timeInterval.stringValue

根据@ onmyway133的回答，这是Swift 4版本：

func format(duration: TimeInterval) -> String {
    let formatter = DateComponentsFormatter()
    formatter.zeroFormattingBehavior = .pad

    if duration >= 3600 {
        formatter.allowedUnits = [.hour, .minute, .second];
    } else {
        formatter.allowedUnits = [.minute, .second];
    }

    return formatter.string(from: duration) ?? "";
}

直接来自苹果文档：在h文件中：

 @property(strong,nonatomic)NSDateComponentsFormatter *timerFormatter;

在m文件中

@synthesize timerFormatter;

- (void)viewDidLoad {
[super viewDidLoad];
NSDateComponentsFormatter *timerFormatter = [[NSDateComponentsFormatter alloc] init];
timerFormatter.unitsStyle = NSDateComponentsFormatterUnitsStylePositional; 
//10:59 Positional THIS ONE DOES NOT SEEM TO WORK iOS<9 WHEN <1Minute JUST SHOWS 01, 10m 59s Abbreviated, 10min 59sec Short, 10minutes 59seconds Full ...
timerFormatter.allowedUnits = NSCalendarUnitHour|NSCalendarUnitMinute|NSCalendarUnitSecond;
}

在需要将NSTimeInterval timeInterval转换为hh：mm：ss字符串的任何地方，请执行以下操作：

NSString *txt=[timerFormatter stringFromTimeInterval:timeInterval];

我想应该将计时器分数淘汰。当Matthias的代码在几秒钟内创建该问题时，我使用了与Matthias稍有不同的以下内容

    - (NSString *)stringFromTimeInterval:(NSTimeInterval)interval {
        int ti = (int) ceil(interval);
        int seconds = ti % 60;
        int minutes = (ti / 60) % 60;
        int hours = (ti / 3600);
        return [NSString stringWithFormat:@"%02d:%02d:%02d",hours, minutes, seconds];
    }

Objective C版本的onmyway133的答案

- (NSString*) formatTimeInterval:(NSTimeInterval) timeInterval {

    NSDateComponentsFormatter *formatter = [[NSDateComponentsFormatter alloc] init];

    formatter.zeroFormattingBehavior = NSDateComponentsFormatterZeroFormattingBehaviorPad;

    if (timeInterval > 3600) {
        formatter.allowedUnits = NSCalendarUnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond;
    } else {
        formatter.allowedUnits = NSCalendarUnitMinute | NSCalendarUnitSecond;
    }

    return [formatter stringFromTimeInterval:timeInterval];
}