NSObject

Introduction#

NSObject is the root class of Cocoa, however the Objective-C language itself does not define any root classes at all its define by Cocoa, Apple’s Framework.This root class of most Objective-C class hierarchies, from which subclasses inherit a basic interface to the runtime system and the ability to behave as Objective-C objects.

This class have all basic property of Objective'C class object like:

self.

class (name of the class).

superclass (superclass of current class).

Syntax#

• self
• superclass
• init
• alloc
• new
• isEqual
• isKindOfClass
• isMemberOfClass
• description

NSObject

@interface NSString : NSObject (NSObject is a base class of NSString class).

You can use below methods for allocation of string class:

- (instancetype)init

+ (instancetype)new

+ (instancetype)alloc

For Copy any object :

- (id)copy;

- (id)mutableCopy;

For compare objects :

- (BOOL)isEqual:(id)object

To get superclass of current class :

superclass

To check which kind of class is this ?

- (BOOL)isKindOfClass:(Class)aClass

Some property of NON-ARC classes:

- (instancetype)retain OBJC_ARC_UNAVAILABLE;

- (oneway void)release OBJC_ARC_UNAVAILABLE;

- (instancetype)autorelease OBJC_ARC_UNAVAILABLE;

- (NSUInteger)retainCount