一、單層數(shù)組的深拷貝

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = UIColor.orangeColor;
    
    TestModel *model1 = [[TestModel alloc] init];
    model1.name = @"zhangsan";
    model1.age = 20;
    
    TestModel *model2 = [[TestModel alloc] init];
    model2.name = @"lisi";
    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);
}

結(jié)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(元素淺拷貝)。

2023-04-19 18:05:19.440437+0800 ArrayDeepCopyDemo dataArr: (
    "<TestModel: 0xxx4c0>",
    "<TestModel: 0xxx680>"
)
2023-04-19 18:05:19.440505+0800 ArrayDeepCopyDemo copyDataArr: (
    "<TestModel: 0xxx4c0>",
    "<TestModel: 0xxx680>"
)
2023-04-19 18:05:19.440542+0800 ArrayDeepCopyDemo deepCopyDataArr: (
    "<TestModel: 0xxx6e0>",
    "<TestModel: 0xxx760>"
)

注意點(diǎn)： TestModel 需要服從NSCopying, NSMutableCopying 協(xié)議

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

@end

@implementation TestModel

- (nonnull id)copyWithZone:(nullable NSZone *)zone {
    TestModel *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、數(shù)組嵌套數(shù)組的深拷貝

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.view.backgroundColor = UIColor.orangeColor;
    
    TestModel *model1 = [[TestModel alloc] init];
    model1.name = @"zhangsna";
    model1.age = 20;
    
    TestModel *model2 = [[TestModel alloc] init];
    model2.name = @"lisi";
    model2.age = 25;
    
    
    NSMutableArray *dataArr = [NSMutableArray array];
    [dataArr addObject:model1];
    [dataArr addObject:model2];
    NSLog(@"dataArr: %@", dataArr);
    
    NSMutableArray *dataList = [NSMutableArray array];
    // 數(shù)組添加數(shù)組
    [dataList addObject:dataArr];
    NSLog(@"dataList: %@", dataList);
    
    // 深拷貝數(shù)組，但是TestModel對(duì)象還是淺拷貝，地址未變化
    NSMutableArray *copyList1 = [[NSMutableArray alloc] initWithArray:dataList copyItems:YES];
    NSLog(@"copyList1: %@", copyList1);
    
    /** 歸檔： TestModel對(duì)象地址變化 */
    NSData *data = [NSKeyedArchiver archivedDataWithRootObject:dataList];
    NSMutableArray *copyList2 = [NSKeyedUnarchiver unarchiveObjectWithData:data];
    NSLog(@"copyList2: %@", copyList2);
}

結(jié)果：dataArr、 dataList、copyList1里面的TestModel地址未變化，copyList2的元素TestModel地址變化。

2023-04-19 18:12:41.609754+0800 ArrayDeepCopyDemo dataArr: (
    "<TestModel: 0xxx2a0>",
    "<TestModel: 0xxx460>"
)
2023-04-19 18:12:41.609822+0800 ArrayDeepCopyDemo dataList: (
        (
        "<TestModel: 0xxx2a0>",
        "<TestModel: 0xxx460>"
    )
)
2023-04-19 18:12:41.609856+0800 ArrayDeepCopyDemo copyList1: (
        (
        "<TestModel: 0xxx2a0>",
        "<TestModel: 0xxx460>"
    )
)
2023-04-19 18:12:41.610019+0800 ArrayDeepCopyDemo copyList2: (
        (
        "<TestModel: 0xxx7e0>",
        "<TestModel: 0xxx800>"
    )
)

注意點(diǎn)： TestModel 需要服從NSCoding 協(xié)議

- (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;
}