ios26--kvc

Posted 2020-10-05 672530440

//
//  main.m
//  13-KVC的使用
//

/**
   KVC: Key Value Coding(键值编码)：1.取值赋值。2.字典转模型。
 */

#import <Foundation/Foundation.h>
#import "XMGPerson.h"
#import "XMGDog.h"

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        /**
          7.取出数组中所有模型的某个属性值
         */
        XMGPerson *person1 = [[XMGPerson alloc] init];
        person1.name = @"zhangsan"; //常规赋值用点语法
        person1.money = 12.99;
        
        XMGPerson *person2 = [[XMGPerson alloc] init];
        person2.name = @"zhangsi";
        person2.money = 22.99;
        
        XMGPerson *person3 = [[XMGPerson alloc] init];
        person3.name = @"wangwu";
        person3.money = 122.99;
        person3.dog.name = @"浩";
        
        NSArray *allPersons = @[person1, person2, person3];
        NSArray *allPersonName = [allPersons valueForKeyPath:@"name"];
        
        NSLog(@"%@", allPersonName);//(zhangsan,zhangsi,wangwu)

        
        /* KVC赋值
        [person1 setValue:@"王五" forKey:@"name"];
        [person1 setValue:@"19" forKeyPath:@"money"]; // 自动类型转换
        NSLog(@"%@-----%.2f", person1.name, person1.money);*/
    }
    return 0;
}

/**
 *  1.把模型转成字典
 */

void test6(){
    XMGPerson *person = [[XMGPerson alloc] init];
    person.name = @"lurry";
    person.money = 21.21;
    
    NSDictionary *dict = [person dictionaryWithValuesForKeys:@[@"name", @"money"]];
    NSLog(@"%@", dict);// {money = "21.21";name = lurry;}

}


/**
 * 2.取值
 */
void test5(){
    XMGPerson *person = [[XMGPerson alloc] init];
    person.name = @"张三";
    person.money = 12332;
    
    // 利用kvc取值，alueForKeyPath和valueForKey一样，
    NSLog(@"%@ --- %.2f", [person valueForKeyPath:@"name"], [[person valueForKey:@"money"] floatValue]);
}

/**
 3.作用: 字典转模型
 开发中是不建议使用setValuesForKeysWithDictionary:
 1> 字典中的key必须在模型的属性中找到
 2> 如果模型中带有模型,setValuesForKeysWithDictionary不好使
 应用场景: 简单的字典转模型 ---> 框架 (MJExtention)
 */
void test4(){
    NSDictionary *dict = @{
                           @"name" :@"lurry",
                           @"money" : @189.88,
                           @"dog" : @{
                                   @"name" : @"wangcai",
                                   @"price" : @8
                                   },
                           @"books": @[
                                   @{@"name" :@"ios快速开发", @"price" : @1999},
                                   @{@"name" :@"iOS快速发", @"price" : @199},
                                   @{@"name" :@"iOS快开发", @"price" : @99}
                                   ]
                           };
    XMGPerson *person = [[XMGPerson alloc] initWithDict:dict];
    NSLog(@"%@", person.dog.class);
    
    [person setValue: @{
                        @"name" : @"wangcai",
                        @"price" : @8
                        } forKeyPath:@"dog"];
}


/**
 *  4.利用KVC修改类的私有成员变量(UIPageControl)
 */
void test3(){
    XMGPerson *person = [[XMGPerson alloc] init];
    // person->_age
    // 利用KVC修改类的私有成员变量
    [person printAge];
    [person setValue:@"88" forKeyPath:@"_age"]; //
    [person setValue:@"88" forKeyPath:@"age"]; //age也可以
    [person printAge];
}

/**
 *  5.利用KVC进行综合赋值
 */
void test2(){
    XMGPerson *person = [[XMGPerson alloc] init];
    person.dog = [[XMGDog alloc] init];
    //        person.dog.name = @"旺财";
    
    // KVC赋值
    /*
     forKey和forKeyPath
     1>forKeyPath 包含了所有 forKey 的功能
     2>forKeyPath 进行内部的点语法,层层访问内部的属性
     3>注意: key值一定要在属性中找到
     */
    [person.dog setValue:@"阿黄" forKey:@"name"];
    [person setValue:@"旺财" forKeyPath:@"dog.name"];
    
    NSLog(@"%@", person.dog.name);

}

/**
 *  6.利用KVC进行简单赋值
 */
void test(){
    XMGPerson *person = [[XMGPerson alloc] init];
    // 常规赋值
    /*
     person.name = @"张三";
     person.age = 18;
     */
    
    // KVC赋值
    [person setValue:@"王五" forKey:@"name"];
    [person setValue:@"19" forKeyPath:@"money"]; // 自动类型转换
    
    NSLog(@"%@-----%.2f", person.name, person.money);
}

//
//  XMGPerson.h
//  13-KVC的使用
//

#import <Foundation/Foundation.h>
@class XMGDog;

@interface XMGPerson : NSObject


/** 姓名 */
@property (nonatomic, copy) NSString *name;//string用copy
/** 钱 */
@property (nonatomic, assign) float money;
/** 狗 */
@property (nonatomic, strong) XMGDog *dog;//自定义类型用strong类型

/** 序号 */
@property (nonatomic, copy) NSString *no;


- (void)printAge;

- (instancetype)initWithDict: (NSDictionary *)dict;
+ (instancetype)personWithDict: (NSDictionary *)dict;

@end

//
//  XMGPerson.m
//  13-KVC的使用
//

#import "XMGPerson.h"

@implementation XMGPerson
{
    int _age;//私有成员变量
}

- (instancetype)init{
    if (self = [super init]) {
        _age = 1;
    }
    return self;
}

- (void)printAge{
    NSLog(@"age:%d", _age);
}

- (NSString *)description{
    return [NSString stringWithFormat:@"name:%@----money:%.2f", _name, _money];
}

- (instancetype)initWithDict:(NSDictionary *)dict{
    if (self = [super init]) {
        /*  有100个要写100个
        self.name = dict[@"name"];
        self.money = [dict[@"money"] floatValue];
         */
        [self setValuesForKeysWithDictionary:dict];
    }
    return self;
}

+ (instancetype)personWithDict:(NSDictionary *)dict{
    return [[self alloc] initWithDict:dict];
}

@end

//
//  XMGDog.h
//  13-KVC的使用
//

#import <Foundation/Foundation.h>

@interface XMGDog : NSObject
/** 姓名 */
@property (nonatomic, copy) NSString *name;
/** 价格 */
@property (nonatomic, assign) float price;
@end

//
//  XMGDog.m
//  13-KVC的使用
//

#import "XMGDog.h"

@implementation XMGDog

@end