OC Basics Review 10-oc ID

ID Type

Data type:

1. Can be used to define variables

2. Can be used as a parameter

3. Can be used as a return value

ID type is a universal pointer (can keep any object's address)

ID equals NSObject *

The nature of the ID typedef struct OBJC_OBJECT *id;

ID is a dynamic type that determines the true type of ID at run time

The ID type can also call private methods

The difference between ID and NSObject *: ID calls subclass-specific methods without forcing type conversions

Note: The ID cannot be appended with * id a = [Animal new]; this one is correct.

OC Basics Review 10-oc ID