内存管理:@class循环引用

  @class循环引用

/*

 1. @class的作用:仅仅告诉编译器,某个名称是一个类

 @class Person; //仅仅告诉编译器,Person是一个类

 

 2.开发中引用一个类的规范

 1> 在.h文件中用@class来声明类

 2> 在.m文件中用#import来包含类的所有东西

 

 3.两端循环引用解决方案

 1> 一端用retain

 2> 一端用assign;

 

 

 */

#import <Foundation/Foundation.h>

#import "Card.h"

@interface Person :NSObject

@property (nonatomic,retain)Card *card;

@end

#import "Person.h"

@implementation Person

- (void)dealloc

{

    NSLog(@"Person类被销毁了!");

    

    [_cardrelease];

    [superdealloc];

}

#import <Foundation/Foundation.h>

@class Person;

@interface Card : NSObject

@property (nonatomic,assign)Person *person;

@end

#import "Card.h"

#import "Person.h"

@implementation Card

- (void)dealloc

{

    NSLog(@"Card被销毁了");

    //[_person release];

    [superdealloc];

}

@end

#import <Foundation/Foundation.h>

#import "Person.h"

int main(int argc,const char * argv[]) {

  

   Person *p = [[Personalloc] init];

    

   Card *c = [[Cardalloc] init];

    //c = 2

    p.card = c;

    

    //p = 1

    c.person = p;

    //p = 0, c = 1

    [prelease];

    //c = 0

    [crelease];

    

   return 0;

}