iOS Collection Utilities

iOS Collection Utilities extend NSArray and NSDictionary functionality via categories. Underlying storage of primitive values BOOL, char, int, float, CGPoint, CGSize, CGRect adhere to NSCoding so collections can be serialized.

• NSDictionary+DotPath - create, access and mutate dictionary values using a dot notation e.g. int age = [dict intForPath:@"person.employee.age"].
• NSArray+Primitive - a convenient way to use NSArray with primitive types e.g. int i = [array intAtIndex:0].
• NSDictionary+Primitive - a convenient way to use NSDictionary with primitive types e.g. int i = [dict intForKey:@"int1"];.

NSDictionary+DotPath

NSDictionary+DotPath extends NSDictionary and NSMutableDictionary to provide support for accessing and mutating nested dictionary values using dot notation. This is very similar to the way a JSON object works. This implementation adds support for BOOL, char, int, float, CGPoint, CGSize, CGRect as well as objects. The following example demonstrates int but all the other types work the same way.

Given nested NSDictionary dict:

dict = {
    int = 0;
    dictLevel1 =     {
        int = 1;
        dictLevel2 =         {
            int = 2;
        };
    };
}

Values can be accessed using a dot notation for the path e.g.

int i = [dict intForPath:@"dictLevel1.dictLevel2.int"]; // i = 2

Values can also be set using a dot notation for the path e.g.

[dict setInt:3 forPath:@"dictLevel1.dictLevel2.newInt"];

Which yields:

dict = {
    int = 0;
    dictLevel1 =     {
        int = 1;
        dictLevel2 =         {
            int = 2;
            newInt = 3;
        };
    };
}

If a nested dictionary doesn't exist or isn't mutable the dictionary is updated. In this example setting an array (myArray) to and undefined dictionary (dictLevel3) creates the dictionary:

NSArray* myArray = @[@"1", @"2"];
[dict setObject:myArray forPath:@"dictLevel1.dictLevel2.dictLevel3.a"];

Which yields:

dict = {
    int = 0;
    dictLevel1 =     {
        int = 1;
        dictLevel2 =         {
            int = 2;
            dictLevel3 =             {
                a = [ 1, 2 ];
            };
            newInt = 3;
        };
    };
}

NSArray+Primitive

NSArray+Primitive extends NSArray and NSMutableArray to provide support for primitives BOOL, char, int, float, CGPoint, CGSize, CGRect. The following example demonstrates int but all the other types work the same way.

NSMutableArray* array = [NSMutableArray array];
[array addInt:1]; // array = [1]
[array addInt:2]; // array = [1, 2]
int i = [array intAtIndex:0]; // i = 1
[array swapIndex1:0 index2:1]; // array = [2, 1]
[array replaceIntAtIndex:0 withInt:3];  // array = [3, 1]
[array insertInt:4 atIndex:1];
NSLog(@"%@", [array description]); // console shows [3, 4, 1]

NSDictionary+Primitive

NSDictionary+Primitive extends NSDictionary and NSMutableDictionary to provide support for primitives BOOL, char, int, float, CGPoint, CGSize, CGRect. The following example demonstrates int but all the other types work the same way.

NSMutableDictionary* dict = [NSMutableDictionary dictionary];
[dict setInt:1 forKey:@"int1"]; // dict = { int1:1 }
[dict setInt:2 forKey:@"int2"]; // dict = { int1:1, int2:2 }
int i = [dict intForKey:@"int1"]; // i = 1
NSLog(@"%@", [dict description]); // console shows { int1 = 1; int2 = 2; }