Tasks

Creating an Array

• + array
• + arrayWithArray:
• + arrayWithContentsOfFile:
• + arrayWithContentsOfURL:
• + arrayWithObject:
• + arrayWithObjects:
• + arrayWithObjects:count:

Initializing an Array

• – initWithArray:
• – initWithArray:copyItems:
• – initWithContentsOfFile:
• – initWithContentsOfURL:
• – initWithObjects:
• – initWithObjects:count:

Querying an Array

• – containsObject:
• – count
• – getObjects:range:
• – lastObject
• – objectAtIndex:
• – objectsAtIndexes:
• – objectEnumerator
• – reverseObjectEnumerator
• – getObjects: Deprecated in iOS 4.0

Finding Objects in an Array

• – indexOfObject:
• – indexOfObject:inRange:
• – indexOfObjectIdenticalTo:
• – indexOfObjectIdenticalTo:inRange:
• – indexOfObjectPassingTest:
• – indexOfObjectWithOptions:passingTest:
• – indexOfObjectAtIndexes:options:passingTest:
• – indexesOfObjectsPassingTest:
• – indexesOfObjectsWithOptions:passingTest:
• – indexesOfObjectsAtIndexes:options:passingTest:
• – indexOfObject:inSortedRange:options:usingComparator:

Sending Messages to Elements

• – makeObjectsPerformSelector:
• – makeObjectsPerformSelector:withObject:
• – enumerateObjectsUsingBlock:
• – enumerateObjectsWithOptions:usingBlock:
• – enumerateObjectsAtIndexes:options:usingBlock:

Comparing Arrays

• – firstObjectCommonWithArray:
• – isEqualToArray:

Deriving New Arrays

• – arrayByAddingObject:
• – arrayByAddingObjectsFromArray:
• – filteredArrayUsingPredicate:
• – subarrayWithRange:

Sorting

• – sortedArrayHint
• – sortedArrayUsingFunction:context:
• – sortedArrayUsingFunction:context:hint:
• – sortedArrayUsingDescriptors:
• – sortedArrayUsingSelector:
• – sortedArrayUsingComparator:
• – sortedArrayWithOptions:usingComparator:

Working with String Elements

• – componentsJoinedByString:

Creating a Description

• – description
• – descriptionWithLocale:
• – descriptionWithLocale:indent:
• – writeToFile:atomically:
• – writeToURL:atomically:

Collecting Paths

• – pathsMatchingExtensions:

Key-Value Observing

• – addObserver:forKeyPath:options:context:
• – removeObserver:forKeyPath:
• – addObserver:toObjectsAtIndexes:forKeyPath:options:context:
• – removeObserver:fromObjectsAtIndexes:forKeyPath:

Key-Value Coding

• – setValue:forKey:
• – valueForKey:

NSArray *myArray;

NSDate *aDate = [NSDate distantFuture];

NSValue *aValue = [NSNumber numberWithInt:5];

NSString *aString = @"a string";

myArray = [NSArray arrayWithObjects:aDate, aValue, aString, nil];

NSString *strings[3];

strings[0] = @"First";

strings[1] = @"Second";

strings[2] = @"Third";

NSArray *stringsArray = [NSArray arrayWithObjects:strings count:2];

// strings array contains { @"First", @"Second" }

NSArray *pathArray = [NSArray arrayWithObjects:@"here", @"be", @"dragons", nil];

NSLog(@"%@",[pathArray componentsJoinedByString:@" "]);

NSArray *mArray = // an array with at least six elements...;

id *objects;

NSRange range = NSMakeRange(2, 4);

objects = malloc(sizeof(id) * range.length);

[mArray getObjects:objects range:range];

for (i = 0; i < range.length; i++) {

    NSLog(@"objects: %@", objects[i]);

}

free(objects);

NSEnumerator *enumerator = [myArray objectEnumerator];

id anObject;

while (anObject = [enumerator nextObject]) {

    /* code to act on each element as it is returned */

}

NSInteger intSort(id num1, id num2, void *context)

{

    int v1 = [num1 intValue];

    int v2 = [num2 intValue];

    if (v1 < v2)

        return NSOrderedAscending;

    else if (v1 > v2)

        return NSOrderedDescending;

    else

        return NSOrderedSame;

}

NSArray *sortedArray; sortedArray = [anArray sortedArrayUsingFunction:intSort context:NULL];

     NSArray *sortedArray =

         [anArray sortedArrayUsingSelector:@selector(caseInsensitiveCompare:)];

NSArray *halfArray;

NSRange theRange;

theRange.location = 0;

theRange.length = [wholeArray count] / 2;

halfArray = [wholeArray subarrayWithRange:theRange];

enum {
   NSBinarySearchingFirstEqual = (1 << 8),
   NSBinarySearchingLastEqual = (1 << 9),
   NSBinarySearchingInsertionIndex = (1 << 10),
};
typedef NSUInteger NSBinarySearchingOptions;