NextDateMatchingDay objective-c方法 - 有沒有比這個代碼更好的方法？

Question

NextDateMatchingDay objective-c方法 - 有沒有比這個代碼更好的方法？

- (NSDate*)NextDateMatchingDay:(NSDateComponents*)dayTime { 
    // Find next date (including date & time) from current date, for which: 
    // (a) the DayOfWeek(no time) matches that dayOfWeek from the input "dateTime" NSDateComponents 
    // (b) the date is > currentDateTime 
    // (c) the final date time will be based on the time passed in by "dateTime" NSDateComponents 
    // e.g. dayTime=Sun10am's, currentDate=Sun1st2pm => result=Sun8th10am 
    // e.g. dayTime=Sun10am's, currentDate=Sun1st9am => result=Sun1st10am 
    // e.g. dayTime=Sun10am's, currentDate=Fri1st1pm => result=Sun8th10am 

    // Prepare 
    NSDate *currDate = [NSDate date]; 
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]; 
    NSDateComponents *addComps = [[[NSDateComponents alloc] init] autorelease]; 

    unsigned unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit; 
    NSDateComponents* currComps = [gregorian components:unitFlags fromDate:currDate]; 

    NSInteger daysCounter = 0; 
    do { 
     [addComps setDay:daysCounter]; 
     NSDate *futureDate = [gregorian dateByAddingComponents:addComps toDate:currDate options:0]; 
     NSDateComponents* futureComps = [gregorian components:unitFlags fromDate:futureDate]; 

     if ([futureComps day] == [currComps day] && [futureComps month] == [currComps month] && [futureComps year] == [currComps year]) 
      return futureDate; 

     daysCounter++;       
    } while (daysCounter < 10);  // just a double check 

    return nil;      // double check - should not get to this 
} 

Answer 1

這似乎是一個改進 - 不知道是否仍然有一種方法可以進一步壓縮，但呢？

+ (NSDate*)NextDateMatchingDay:(NSDateComponents*)dayTime sourceDate:(NSDate*)sourceDate { 
    // Find next date (including date & time) from current date, for which: 
    // (a) the DayOfWeek(no time) matches that dayOfWeek from the input "dateTime" NSDateComponents 
    // (b) the date is > currentDateTime 
    // (c) the final date time will be based on the time passed in by "dateTime" NSDateComponents 
    // e.g. dayTime=Sun10am's, currentDate=Sun1st2pm => result=Sun8th10am 
    // e.g. dayTime=Sun10am's, currentDate=Sun1st9am => result=Sun1st10am 
    // e.g. dayTime=Sun10am's, currentDate=Fri1st1pm => result=Sun8th10am 

    NSDate *returnDate = [sourceDate dateWithHoursMinsSecsComps:dayTime]; 

    // Check if is same day 
    NSInteger configDOW = [dayTime weekday]; 
    NSInteger sourceDOW = [sourceDate dayOfWeek]; 
    if (configDOW == sourceDOW) { 

     // source date is already the correct day - but is it before or after 
     if ([returnDate isBeforeThisDate:sourceDate]) { 
      // can't be source Date - so move forward 7 days 
      returnDate = [returnDate dateByAddingDays:7]; 
      return returnDate; 
     } else { 
      // can be source Date (with new time) 
      return returnDate; 
     } 
    } 

    // source day is on another day-of-week other than the dayTime provided value 
    NSInteger dayOfWeekDiff = (7 + (configDOW - sourceDOW)) % 7; 

    returnDate = [returnDate dateByAddingDays:dayOfWeekDiff]; 
    return returnDate; 
}