objective－c学习笔记

创建一个类

需要先有一个类描述：

#import <Foundation/Foundation.h>

@interface User : NSObject {

int uid;

int age;

NSString *name;

}

-(void)print;

-(void)setId : (int) uid;

-(void)setAge : (int) age;

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

-(NSString *)getName;

@end

#import <Foundation/Foundation.h>

#import "User.h"

@implementation User

-(void)print

{

NSLog(@"this id is %d, age is %d and name is %@",uid, age,name);

}

//实现interface中带参数的方法时，参数名称不能与interface中定义的变量名称一样

-(void)setId:(int)value

{

uid = value;

}

-(void)setAge:(int)value

{

age = value;

}

-(void)setName:(NSString *)value

{

name = value;

}

-(NSString *)getName

{

return name;

}

@end

实例化一个对象：

User *u = [User new];或者是User *u = [[User alloc] init];

两种创建方式结果一样，调用alloc后调用init的方式貌似可以自定义构造方法，没有具体实验。