Objective-C：ARC自动释放对象内存

ARC是cocoa系统帮你完成对象内存释放的引用计数机制

　　　　.h文件

//  Person.h
//  01-ARC
//
//  Created by ma c on 15/8/13.
//  Copyright (c) 2015年. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface Person : NSObject
@property(nonatomic,strong)NSString *name;
@property(nonatomic,assign)NSInteger age;
+(Person*)personWithName:(NSString*) name andAge:(NSInteger) age;
-(id)initWithName:(NSString*) name andAge:(NSInteger) age;
-(void)show;
@end

　　　　.m文件

//  Person.m
//  01-ARC
//
//  Created by ma c on 15/8/13.
//  Copyright (c) 2015年. All rights reserved.
//

#import "Person.h"

@implementation Person
-(id)initWithName:(NSString*) name andAge:(NSInteger) age
{
    self = [super init];
    if(self)
    {
        _name = name;
        _age = age;
    }
    return self;
}

/*
 在类方法中，由于没有创建对象实例，所以：self指针不能用，实例变量不能用。
 */
+(Person*)personWithName:(NSString*) name andAge:(NSInteger) age
{
    return [[Person alloc]initWithName:name andAge:age];
}

-(void)show
{
    NSLog(@"name:%@,age:%ld",_name,_age);
}

/*
创建对象时是先创建父类的部分,再创建子类的部分；
 销毁对象时，顺序正好相反
 ARC禁止显式的发送dealloc消息
*/
-(void)dealloc
{
    NSLog(@"person dealloc");
    //[super dealloc]; //禁止显式的发送dealloc消息
}
@end

　　　　主函数测试

//  main.m
//  01-ARC
//
//  Created by ma c on 15/8/13.
//  Copyright (c) 2015年. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "Person.h"
int main(int argc, const char * argv[])
{
    @autoreleasepool
    {
        Person *person = [[Person alloc]initWithName:@"Jim" andAge:22];
        
        [person show];
        //[person dealloc];//error,底层会自动调用该方法用来销毁对象
    }
    return 0;
}

　　　　测试结果：

2015-08-13 17:48:54.904 01-ARC[1636:107161] name:Jim,age:22
2015-08-13 17:48:54.905 01-ARC[1636:107161] person dealloc
Program ended with exit code: 0