iOS复习笔记8:autorelease详解

标签：objective-c   内存管理   ios   

// Person.h


@interface Person


@property(nonatomic, assign) int age;


@end

// Person.m
#improt <Foundation/Foundation.h>


@implementation Person


- (void)dealloc()
{	
	NSLog(@"Person dealloc");
	[super dealloc];
}


@end

// main.m
#improt <Foundation/Foundation.h>
#improt "Person.h"


int main()
{
	@autorelease
	{// 创建了一个自动释放池
		Person* person1 = [[[Person alloc] init] autorelease];
		person1.age = 25;
	}// 释放池销毁，这一行之后会打印出:"Person dealloc"
		


	// 释放池个数不限
	@autorelease
	{
		Person* person2 = [[[Person alloc] init] autorelease];
		person2.age = 25;


		// 释放池可以嵌套
		@autorelease
		{
			Person* person3 = [[[Person alloc] init] autorelease];
			person3.age = 25;
		}
	}


	// 另一种创建方式
	NSAutoreleasePool* p = [[NSAutoreleasePool alloc] init];// 创建了一个自动释放池
	Person* person4 = [[[Person alloc] init] autorelease];
	person4.age = 25;
	[pool release];// 释放池销毁


	return 0;
}

@autorelease{
// 释放池内对象
}

NSAutoreleasePool* p = [[NSAutoreleasePool alloc] init];// 创建了一个自动释放池
// 释放池内对象
[pool release];

Person* person2 = [[[Person alloc] init] autorelease];
[person2 autorelease];

Person* person2 = [[[[Person alloc] init] autorelease] autorelease];

Person* person2 = [[[Person alloc] init] autorelease];
[person2 release];

// Person.h


@interface Person


@property(nonatomic, assign) int age;


+ (id)person;
+ (id)personWithAge:(int)age;


@end

// Person.m
#improt <Foundation/Foundation.h>


@implementation Person


// 快速返回一个自动释放的对象
+ (id)person
{
	retur [Person alloc] init] autorelease];
}


+ (id)personWithAge:(int)age
{
	Person* p = [Person alloc] init] autorelease];
	p.age = age
	retur p;
}

@end

// main.m
#improt <Foundation/Foundation.h>
#improt "Person.h"


int main()
{
	@autorelease{
		Person* p1 = [Person person];
		p1.age = 22;
		Person* p1 = [Person personWithAge:25];


		// 类似的系统方法
		NSString* str = [NSString stringWithFormat("%d to string",2)];
		NSNumber* n = [NSNumber numberWithInt:100];
	}


	retur 0;
}

// Student.h
@interface Student:Person
@property(nonatomic, assign) int grade;
@end

// Student.m
#improt <Foundation/Foundation.h>


@implementation Student
@end

// main.m
#improt <Foundation/Foundation.h>
#improt "Person.h"


int main()
{
	@autorelease{
		Student* s = [Student personWithAge:10];
		s.grade = 1;// 报错
	}


	retur 0;
}

+ (id)person
{
	// 改为self后返回调用者的实例
	retur [self alloc] init] autorelease];
}


+ (id)personWithAge:(int)age
{
	Person* p = [self alloc] init] autorelease];
	// 设置父类(Person)的age值
	p.age = age
	retur p;
}

iOS复习笔记8:autorelease详解

标签：objective-c   内存管理   ios   

原文地址：http://blog.csdn.net/xufeng0991/article/details/43302993