RunTime进行归档反归档实现深拷贝

新建NSObject分类NSObject+Encode

在分类中重写NSObject的编码反编码方法

• (void)encodeWithCoder:(NSCoder *)aCoder;

• -(instancetype)initWithCoder:(NSCoder *)aDecoder;

在NSObject+Encode.m中 引入 #import <objc/runtime.h>

---

代码如下:

#import "NSObject+Encode.h"
#import <objc/runtime.h>

@implementation NSObject (Encode)

- (void)encodeWithCoder:(NSCoder *)aCoder{
    
    // 得到实例变量链表
    // 创建ivarCount保存实例变量个数
    unsigned int ivarCount = 0;
    Ivar *vars = class_copyIvarList([self class], &ivarCount);
    
    // 循环遍历实例变量链表
    for (int i = 0; i < ivarCount; i++) {
        
        // 获得实例变量名
        NSString *varName = [NSString stringWithUTF8String:ivar_getName(vars[i])];
        
        // 通过KVC获取实例变量的值
        id value = [self valueForKey:varName];
        
        // 对此值,以实例变量名作为key进行归档
        [aCoder encodeObject:value forKey:varName];
    }
    
    free(vars);
}

-(instancetype)initWithCoder:(NSCoder *)aDecoder{
    
    // 初始化方法
    self = [self init];
    
    if (self) {
       // 获取实例变量链表
        unsigned int ivarCount = 0;
        
        Ivar *vars = class_copyIvarList([self class], &ivarCount);
        
        // 循环遍历实例变量链表
        for (int i = 0; i < ivarCount; i++) {
            
            // 获得实例变量名
            NSString *varName = [NSString stringWithUTF8String:ivar_getName(vars[i])];
            
            // 以实例变量名为key进行反归档
            id value = [aDecoder decodeObjectForKey:varName];
            
            // 通过KVC对此对象的实例变量进行赋值
            [self setValue:value forKey:varName];
            

        }
        
        free(vars);
    }
    
    return self;
    
}

@end

新建Student类声明两个属性

@property(nonatomic,strong)NSString *name;
@property(nonatomic,assign) NSInteger age;

对Student进行归档反归档

    Student *stu = [[Student alloc]init];
    
    stu.name = @"zhang";
    stu.age = 26;
    
    // 进行归档
    NSData *data = [NSKeyedArchiver archivedDataWithRootObject:stu];
    
    // 进行反归档
    Student *stu2 = [NSKeyedUnarchiver unarchiveObjectWithData:data];
    
    NSLog(@"stu:%@,%ld",stu.name,stu.age);
    NSLog(@"stu2:%@,%ld",stu2.name,stu2.age);
    
    NSLog(@"=======");
    stu.name = @"李四";
    stu.age = 100;
    
    NSLog(@"stu:%@,%ld",stu.name,stu.age);
    NSLog(@"stu2:%@,%ld",stu2.name,stu2.age);

运行结果:

Demo下载