OC variable scope

# Import <Foundation/Foundation. h>

@ Interface person: nsobject

{

Int _ age; // The default value of the variable in @ interface is @ public.

@ Protected

Int _ height; // It can only be accessed in the object methods of the current class and subclass.

@ Pritate

Int _ weight; // can be accessed directly only in the object method of the current class

@ Package

Nsstring * _ name; // it can only be used within the current framework

}

-(INT) age;

-(Void) setage :( INT) age;

-(INT) height;

-(Void) setheight :( INT) height;

-(INT) weight;

-(Void) setweight :( INT) weight;

-(Nsstring *) Name;

-(Void) setname :( nsstring *) Name;

@ End

@ Implementation person

{

Nsstring * birthday; // The default value of the variable in @ implementation is @ private.

}

-(INT) Age

{

Return-age

}

-(Void) setage :( INT) Age

{

-Age = age;

}

-(INT) Height

{

Return _ height;

}

-(Void) setheight :( INT) Height

{

-Height = height;

}

-(INT) Weight

{

Return _ weight;

}

-(Void) setweight :( INT) Weight

{

_ Weight = weight;

}

-(Nsstring *) Name

{

Return _ name;

}

-(Void) setname :( nsstring *) Name

{

_ Name = Name;

}

@ End

1 @ public (public) can be directly accessed anywhere on the premise of an object.

2 @ protected (protected) can only be accessed in the object methods of the current class and subclass

3 @ private (private) can only be accessed directly in the object method of the current class

4 @ package (Framework-level) the scope is between private and public. You can directly ask by variable name as long as you are in the same framework.

5 @ InterfaceBy default, the declared member variables are public, and the member variables declared in @ implatation are private.

 

OC variable scope