Objective-c:arc automatically frees object memory

ARC is a reference counting mechanism that cocoa system helps you to complete object memory release

. h file

 
1 //  Person.h
 2 //  01-ARC
 3 //
 4 //  Created by ma c on 15/8/13.
 5 //  Copyright (c) 2015年 bjsxt. All rights reserved.
 6 //
 7 
 8 #import <Foundation/Foundation.h>
 9 
10 @interface Person : NSObject
11 @property(nonatomic,strong)NSString *name;
12 @property(nonatomic,assign)NSInteger age;
13 +(Person*)personWithName:(NSString*) name andAge:(NSInteger) age;
14 -(id)initWithName:(NSString*) name andAge:(NSInteger) age;
15 -(void)show;
16 @end

    . m file

 
1 // Person.m
 2 // 01-ARC
 3 //
 4 // Created by ma c on 15/8/13.
 5 // Copyright (c) 2015 bjsxt. All rights reserved.
 6 //
 7
 8 #import "Person.h"
 9 
10 @implementation Person
11-(id) initWithName: (NSString *) name andAge: (NSInteger) age
12 {
13 self = [super init];
14 if (self)
15 {
16 _name = name;
17 _age = age;
18}
19 return self;
20}
twenty one 
twenty two /*
23 In the class method, since no object instance is created, the self pointer cannot be used, and the instance variable cannot be used.
twenty four  */
25 + (Person *) personWithName: (NSString *) name andAge: (NSInteger) age
26 {
27 return [[Person alloc] initWithName: name andAge: age];
28}
29
30-(void) show
31 {
32 NSLog (@ "name:% @, age:% ld", _ name, _age);
33}
34
35 / *
36 When creating an object, first create the part of the parent class, and then create the part of the subclass;
37 When destroying objects, the order is reversed
38 ARC forbids sending explicit dealloc messages
39 * /
40-(void) dealloc
41 {
42 NSLog (@ "person dealloc");
43 // [super dealloc]; // Forbid sending explicit dealloc messages explicitly
44}
45 @end

    Main function test

1 // main.m
  2 // 01-ARC
  3 //
  4 // Created by ma c on 15/8/13.
  5 // Copyright (c) 2015 bjsxt. All rights reserved.
  6 //
  7
  8 #import <Foundation / Foundation.h>
  9 #import "Person.h"
10 int main (int argc, const char * argv [])
11 {
12 @autoreleasepool
13 {
14 Person * person = [[Person alloc] initWithName: @ "Jim" andAge: 22];
15
16 [person show];
17 // [person dealloc]; // error, the bottom layer will automatically call this method to destroy the object
18}
19 return 0;
20} 

Test results:

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

Objective-c:arc automatically frees object memory