@property和@synthesize

 

#import <Foundation/Foundation.h>

 

@interface Person : NSObject

{

    int _age;

    // int age;

    

    int _height;

    

    double _weight;

    

    NSString *_name;

}

 

// @property：可以自动生成某个成员变量的setter和getter声明

@property int age;

//- (void)setAge:(int)age;

//- (int)age;

 

 

@property int height;

//- (void)setHeight:(int)height;

//- (int)height;

 

- (void)test;

 @property double weight;

 @property NSString *name;

 @end

 

#import "Person.h"

 

@implementation Person

 

// @synthesize自动生成age的setter和getter实现，并且会访问_age这个成员变量

@synthesize age = _age;

 

@synthesize height = _height;

 

@synthesize weight = _weight, name = _name;

 

@end

 

#import <Foundation/Foundation.h>

 

@interface Car : NSObject

{

    //int _speed;

    //int _wheels;

}

@property int speed;

@property int wheels;

 

//@property int speed, wheels;

- (void)test;

@end

 

#import "Car.h"

 

@implementation Car

//@synthesize speed = _speed, wheels = _wheels;

// 会访问_speed这个成员变量，如果不存在，就会自动生成@private类型的_speed变量

@synthesize speed = _speed;

@synthesize wheels = _wheels;

 

 

- (void)test

{

    NSLog(@"速度=%d", _speed);

}

 

@end

 

 

#import <Foundation/Foundation.h>

 

@interface Dog : NSObject

@property int age;

@end

 

 

#import "Dog.h"

 

@implementation Dog

 

 

- (void)setAge:(int)age

{

 

}

 

//- (int)age

//{

//    

//}

 

//- (int)age

//{

//    return 10;

//}

 

@end

 

#import <Foundation/Foundation.h>

 

@interface Cat : NSObject

{

    //int _age;

    //int age;

}

@property int age;

@end

 

 

#import "Cat.h"

 

@implementation Cat

 

// 默认会访问age这个成员变量，如果没有age，就会自动生成@private类型的age变量

@synthesize age;

 

 

@end

 

#import <Foundation/Foundation.h>

#import "Person.h"

#import "Cat.h"

#import "Dog.h"

 

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

{

 

    @autoreleasepool {

        Dog *d = [Dog new];

        

        d.age = 5;

        

        NSLog(@"%d", d.age);

    }

    return 0;

}