OBJECTIVE-C member variables

Access permissions for member variables

The member variables in OBJECTIVE-C have the following three properties

• Public (external and sub-class accessible)
• Protected (sub-class accessible, externally inaccessible)
• Private (external and sub-class inaccessible)

By default, the protected property

Example: Class A has 3 properties, Class B is a subclass of Class A, and the main function is external to class A.

A.h

@interface a:nsobject{@public    int Publicvar; @protected    int Protectedvar; @private    int Privatevar;} @end

Main.m

int Main (intconstChar * argv[]) {    @autoreleasepool    {        *a = [[A alloc] init];        A1;       // OK        2;    // Error Compilation But        3;      // Error Compilation But     }    return0;}

B.m

@implementation B-(void) f{    *b = [[[B alloc] init];    b1;       // OK    2;    // OK    3;      // Error Compilation But }@end

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OBJECTIVE-C member variables