Class level access

Objective-C provides facility of class level access. In the examples given above we have used '-' sign before method, '-' means instance level access. Now we will see how to define method that can be access on class level.

MyClass.h


#import<Foundation/NSObject.h>

@interface MyClass:NSObject {

}
   -(void)instanceShow;
   +(void)classShow;

@end

MyClass.m


#import<stdio.h>
#import"MyClass.h"
@implementation MyClass
    -(void)instanceShow {
    printf("This is instance 
level method.\n");
}

    +(void)classShow {
    printf("This is class
 level method.");
}
@end

MyClassMain.m


#import<stdio.h>
#import"MyClass.m"
int main(){
MyClass *instance = [
  [MyClass alloc]init];
[instance instanceShow];

[MyClass classShow];
[instance release];
return ;
}

Output:

This is instance level method.
This is class level method.

Here in this example we have created a method named 'classShow' that can be accessed on class level means no need to create object to use classShow() method. We can directly use this method through class name. +(void)init method is called when objective-C program starts and it calls for every class so it is the better place to define class level variable.

Related Tags for Class level access:

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