Question

I’ve this model:

@interface Data : NSObject
@property int Period; 
@property (nonatomic, assign) NSDate *Start;
@property (nonatomic, assign) NSDate *End;
@end

@implementation Data
@synthesize Period, Start, End;
@end

I add data in mutable array.

@property (strong, nonatomic) NSMutableArray* myArray;
self.myArray = [NSMutableArray arrayWithCapacity:0];

Data *element1 =[ [Data alloc] init];
element1.Period = 1;
element1.Start = dateStart1;
element1.End = dateEnd1;
[self.myArray addObject:element1];

Data *element2 =[ [Data alloc] init];
element2.Period = 2;
element2.Start = dateStart2;
element2.End = dateEnd2;
[self.myArray addObject:element2];

Data *element3 =[ [Data alloc] init];
element3.Period = 3;
element3.Start = dateStart3;
element3.End = dateEnd3;
[self.myArray addObject:element3];

I can extract Start dates from array

Data * extractDateStart = [self.myArray valueForKey:@"Start"];
NSLog(@"All Start Dates: %@", extractDateStart);

I need to cycle for that array to search in which of the three period a specific date (inserted by user) is.

I know how to extract data from ‘normal’ array:

for(NSString * extractDate in self.myArray) {
    NSLog(extractDate);
}

And know too how to compare one date with another:

  switch ([dateInserted compare: date]) {
    case NSOrderedAscending:
        // dateInserted old than date
      break;
    case NSOrderedSame:
        // dateInserted the same then date
      break;
    case NSOrderedDescending:
        // dateInserted new then date 
      break;
    default:
        // generic error
      break;
}

But how to move in this case ?

Answer 1

I might not understand your question, but it sounds like you:

• Have a user provided NSDate
• Want to find the Data object for which the NSDate falls between the Start and End dates

If that’s the case, something like this should work:

NSDate *dateToFind = ...;
Data *foundData = nil; // We will put the correct Data object here if we find it    

for (Data *data in self.myArray) {
    // Test that dateToFind is between data.Start and data.End
    if (([dateToFind compare:data.Start] != NSOrderedAscending) 
            && ([dateToFind compare:data.End] != NSOrderedDescending)))
    {
        foundData = data; // dateToFind is in this Data's date range
    }
}

// foundData is either nil or contains the Data you were looking for

For other good ways to test if a date falls between two other dates, see this question.