ios - NSDateFormatter 的时间间隔不正确

Question

我有以下方法将持续时间（以秒为单位）格式化为格式为@“mm：ss”的字符串。每当输入特定值 60 时，此方法的行为都出乎意料：

• 持续时间 = 59 -> @"00:59"
• 持续时间 = 60 -> @"59:59"（预期为 @"01:00"）
• 持续时间 = 61 -> @"01:01"

方法：

+ (NSString *)formatDuration:(NSTimeInterval)duration
{    
    NSDateFormatter *durationFormatter = [[NSDateFormatter alloc] init];
    [durationFormatter setDateFormat:@"mm:ss"];

    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *zeroComponents = [[NSDateComponents alloc] init];
    zeroComponents.hour = 0;
    zeroComponents.minute = 0;
    zeroComponents.second = 0;

    NSDate *zeroDate = [calendar dateFromComponents:zeroComponents];
    [zeroComponents release];
    NSDate *endDate = [NSDate dateWithTimeInterval:duration sinceDate:zeroDate];

    return [[durationFormatter autorelease] stringFromDate:endDate];
}