如何正确找到此代码中的时差？

Question

我想比较当前时间10:15的时间，然后找到差异即。时间为10点15分。一切编译，但我总是得到75 ....有人可以帮忙吗？如果可能，我会非常喜欢编码示例。此外，我试图使用 - （时间间隔）timeIntervalSinceNow，但我无法弄清楚如何工作，所以如果任何人也有这样的解释，我会非常感谢 *注意我使用的是版本3.2.6，请指教因此，谢谢

NSDate *today = [NSDate date]; 
NSCalendar *gregorian = [[NSCalendar alloc] 
            initWithCalendarIdentifier:NSGregorianCalendar]; 
NSDateComponents *components = 
[gregorian components:(NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit) fromDate:today]; 

NSInteger hour = [components hour]; 
NSInteger minute = [components minute]; 
NSInteger second = [components second]; 


NSInteger combo = hour + (minute/60) + (second/3600); 

NSTimeInterval time = combo*60*60; 

NSTimeInterval tenFifteenFirstPeriodStop = 10.25*60*60; 

    double myDouble; 
int myInt; 
NSString* myNewString; 
NSString *info; 



      if(time <tenFifteenFirstPeriodStop){ 
     myDouble = (tenFifteenFirstPeriodStop-time)/60; 
     myInt = (int)(myDouble + (myDouble>0 ? 0.5 : -0.5)); 
     myNewString = [NSString stringWithFormat:@"%d", myInt]; 
     info = [[NSString alloc] initWithFormat: 
     @"%@",myNewString]; 
     } 

      NSString *message = [[NSString alloc] initWithFormat: 
        @"%@", info]; 

    UIAlertView *alert =[[UIAlertView alloc] initWithTitle:@"Minutes Until the Bell   Rings" message:message delegate:nil cancelButtonTitle:@"Great!" otherButtonTitles:nil]; 
[alert show]; 
[alert release]; 
[message release]; 

Answer 1

这会给你秒钟的时间，直到今天10.15。如果它已经通过，它将显示明天10.15秒的时间。

NSDate *today = [NSDate date]; 
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]; 
NSDateComponents *components = [gregorian components:(NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) 
              fromDate:today]; 
[components setMinute:15]; 
[components setHour:10]; 

NSDate * tenFifteenToday = [gregorian dateFromComponents:components]; 
if ([tenFifteenToday timeIntervalSinceNow] < 0) { 
    NSDateComponents * daysToAdd = [[[NSDateComponents alloc] init] autorelease]; 
    [daysToAdd setDay:1]; 

    NSDate * tenFifteenTomorrow = [gregorian dateByAddingComponents:daysToAdd toDate:tenFifteenToday options:0]; 
    NSLog(@"%.0lf", [tenFifteenTomorrow timeIntervalSinceNow]); 
} else { 
    NSLog(@"%.0lf", [tenFifteenToday timeIntervalSinceNow]); 
}