深拷贝数组中的模型

一、单层数组的深拷贝

---

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = UIColor.orangeColor;
    
    PersonModel *model1 = [[PersonModel alloc] init];
    model1.name = @"李";
    model1.age = 20;
    
    PersonModel *model2 = [[PersonModel alloc] init];
    model2.name = @"杨";
    model2.age = 25;
    
    
     NSMutableArray *dataArr = [NSMutableArray array];
    [dataArr addObject:model1];
    [dataArr addObject:model2];
    NSLog(@"dataArr: %@", dataArr);
    NSMutableArray *copyDataArr = [NSMutableArray arrayWithArray:dataArr];
    NSLog(@"copyDataArr: %@", copyDataArr);
    NSMutableArray *deepCopyDataArr = [[NSMutableArray alloc] initWithArray:dataArr copyItems:YES];
    NSLog(@"deepCopyDataArr: %@", deepCopyDataArr);
}

结果：deepCopyDataArr 和 dataArr中的元素地址不同,copyDataArr 和 dataArr中的元素地址仍然相同(元素浅拷贝)。

2023-04-19 18:05:19.440437+0800 ArrayDeepCopyDemo[13315:5896086] dataArr: (
    "<PersonModel: 0x2823674c0>",
    "<PersonModel: 0x282367680>"
)
2023-04-19 18:05:19.440505+0800 ArrayDeepCopyDemo[13315:5896086] copyDataArr: (
    "<PersonModel: 0x2823674c0>",
    "<PersonModel: 0x282367680>"
)
2023-04-19 18:05:19.440542+0800 ArrayDeepCopyDemo[13315:5896086] deepCopyDataArr: (
    "<PersonModel: 0x2823676e0>",
    "<PersonModel: 0x282367760>"
)

注意点： PersonModel 需要服从NSCopying, NSMutableCopying 协议

@interface PersonModel () <NSCopying, NSMutableCopying, NSCoding>

@end

@implementation PersonModel

- (nonnull id)copyWithZone:(nullable NSZone *)zone {
    PersonModel *model = [[self class] allocWithZone:zone];
    model.name = self.name;
    model.age = self.age;
    return model;
}

- (nonnull id)mutableCopyWithZone:(nullable NSZone *)zone {
    return [self copyWithZone:zone];
}

@end

二、数组嵌套数组的深拷贝

---

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = UIColor.orangeColor;
    
    PersonModel *model1 = [[PersonModel alloc] init];
    model1.name = @"李";
    model1.age = 20;
    
    PersonModel *model2 = [[PersonModel alloc] init];
    model2.name = @"杨";
    model2.age = 25;
    
    
    NSMutableArray *dataArr = [NSMutableArray array];
    [dataArr addObject:model1];
    [dataArr addObject:model2];
    NSLog(@"dataArr: %@", dataArr);
    
    NSMutableArray *dataList = [NSMutableArray array];
    // 数组添加数组
    [dataList addObject:dataArr];
    NSLog(@"dataList: %@", dataList);
    
    // 深拷贝数组，但是PersonModel对象还是浅拷贝，地址未变化
    NSMutableArray *copyList1 = [[NSMutableArray alloc] initWithArray:dataList copyItems:YES];
    NSLog(@"copyList1: %@", copyList1);
    
    /** 归档： PersonModel对象地址变化 */
    NSData *data = [NSKeyedArchiver archivedDataWithRootObject:dataList];
    NSMutableArray *copyList2 = [NSKeyedUnarchiver unarchiveObjectWithData:data];
    NSLog(@"copyList2: %@", copyList2);
}

结果：dataArr、 dataList、copyList1里面的PersonModel地址未变化，copyList2的元素PersonModel地址变化。

2023-04-19 18:12:41.609754+0800 ArrayDeepCopyDemo[13324:5898549] dataArr: (
    "<PersonModel: 0x282b852a0>",
    "<PersonModel: 0x282b85460>"
)
2023-04-19 18:12:41.609822+0800 ArrayDeepCopyDemo[13324:5898549] dataList: (
        (
        "<PersonModel: 0x282b852a0>",
        "<PersonModel: 0x282b85460>"
    )
)
2023-04-19 18:12:41.609856+0800 ArrayDeepCopyDemo[13324:5898549] copyList1: (
        (
        "<PersonModel: 0x282b852a0>",
        "<PersonModel: 0x282b85460>"
    )
)
2023-04-19 18:12:41.610019+0800 ArrayDeepCopyDemo[13324:5898549] copyList2: (
        (
        "<PersonModel: 0x282b857e0>",
        "<PersonModel: 0x282b85800>"
    )
)

注意点： PersonModel 需要服从NSCoding 协议

- (void)encodeWithCoder:(nonnull NSCoder *)coder {
    [coder encodeObject:_name forKey:@"name"];
    [coder encodeInteger:_age forKey:@"age"];
}

- (nullable instancetype)initWithCoder:(nonnull NSCoder *)coder {
    if (self = [super init]) {
        _name = [coder decodeObjectForKey:@"name"];
        _age = [coder decodeIntForKey:@"age"];
    }
    return self;
}