OC基础 点语法的使用

1.创建一个Student类继承于NSObject，Student.h文件

#import <Foundation/Foundation.h>

@interface Student : NSObject

{

    NSString *_name;

    NSString *_nickName;

}

//@property定义属性

//1,它给该类声明了一个属性名＋下划线的变量

//2,它给该类声明了一个getter方法和一个setter方法

//修饰符

//atomic和nonatomic

//原子性和非原子性,atomic线程安全，nonatomic线程不安全

//一般情况下使用nonatomic

//setter修饰符指定赋值时调用哪个方法来实现setter

//setter修饰符指定读取值时调用哪个方法来实现getter

@property (nonatomic,setter = setNickName:,getter = nickName) NSString *nickName;

//修饰符

//assign用来修饰基本类的

//strong或者retain是用来修饰对象指针的

//readonly只读:只声明和实现getter，不声明和实现setter方法

//readwrite可读写:声明和实现了getter和setter，默认就是readwrite

@property (assign,readonly) int age;

@property (retain,readwrite) NSString *secondName;

-(void)setName:(NSString *)name;

-(NSString *)getName;

-(void)setaaa:(NSString *)aaa;

@end

2.Student.m文件

#import "Student.h"

@implementation Student

//@synthesize在.m文件内为属性添加setter和getter方法的实现

//@synthesize nickName;

-(void)setName:(NSString *)name

{

    _name = name;

}

-(NSString *)getName

{

    return _name;

}

-(void)setNickName:(NSString *)nickName

{

    _nickName = nickName;

    self.nickName = nickName;

}

-(void)setaaa:(NSString *)aaa

{

}

3.创建Teacher类继承于NSObject，Teacher.h文件

#import <Foundation/Foundation.h>

#import "Student.h"

@interface Teacher : NSObject

@property Student *stu;

@end

Teacher.m文件

#import "Teacher.h"

@implementation Teacher

@end

4.点语法的使用

        Student *stu = [[Student alloc] init];

        [stu setName:@"zhangsan"];

        NSString *name = [stu getName];

        NSLog(@"%@",name);

        //属性名在=的左侧，代表赋值，实际是调用类的setter方法

        stu.nickName = @"xiaozhang";

        //属性名在＝的右侧，代表读取值,实际是调用类的getter方法

        NSLog(@"%@",stu.nickName);

        Teacher *tea = [[Teacher alloc] init];

        tea.stu = stu;