OC 언어-08-심층 복사 및 얕은 복사 상해(예)

- (void)imutableInstanceCopy
{
    NSString *string = @"Welcome to Xcode";

    //copy，   
    NSString *stringCopy = [string copy];
    //mutableCopy，       
    NSMutableString *stringMutableCopy = [string mutableCopy];
    [stringMutableCopy appendString:@"!"];

    //string stringCopy       
    NSLog(@"string: %p", string);
    NSLog(@"strongCopy: %p", stringCopy);

    //string stringMutableCopy       ，       
    NSLog(@"stringMCopy:%p", stringMutableCopy);
}

- (void)mutableInstanceCopy
{
    NSMutableString *mutableString = [NSMutableString stringWithString: @"Welcome to Xcode"];

    //   ，       
    NSString *stringCopy = [mutableString copy];
    NSMutableString *mutableStringCopy = [mutableString copy];
    //   ，     ，    “Attempt to mutate immutable object with appendString:”
    [mutableStringCopy appendString:@"~~~"];

    //   ，      
    NSMutableString *stringMutableCopy = [mutableString mutableCopy];
    [stringMutableCopy appendString:@"!"];

    //   mutableString        
    NSLog(@"mutableString: %p", mutableString);
    NSLog(@"string: %p", stringCopy);
    NSLog(@"mutableStringCopy: %p", mutableStringCopy);
    NSLog(@"stringMutbleCopy:%p", stringMutableCopy);
}

- (void)containerInstanceShallowCopy
{
    NSArray *array = [NSArray arrayWithObjects:[NSMutableString stringWithString:@"Welcome"],@"to",@"Xcode",nil];

    //   
    NSArray *arrayCopy = [array copy];
    //   
    NSMutableArray *arrayMutableCopy = [array mutableCopy];

    NSLog(@"array: %p", array);
    NSLog(@"arrayCopy: %p", arrayCopy);
    NSLog(@"arrayMutableCopy: %p", arrayMutableCopy);

    //          ，           
    NSMutableString *testString = [array objectAtIndex:0];
    [testString appendString:@" you"];

    //           
    NSLog(@"array[0]: %@", array[0]);
    NSLog(@"arrayCopy[0]: %@", arrayCopy[0]);
    NSLog(@"arrayMutableCopy[0]: %@", arrayMutableCopy[0]);
}

- (void)containerInstanceDeepCopy
{
    NSArray *array = [NSArray arrayWithObjects:[NSMutableString stringWithString:@"Welcome"],@"to",@"Xcode",nil];

    //          
    NSArray *deepCopyArray = [[NSArray alloc] initWithArray:array];
    //        ，          
    NSArray *trueDeepCopyArray = [NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:array]];

    NSLog(@"array: %p", array);
    NSLog(@"deepCopyArray: %p", deepCopyArray);
    NSLog(@"trueDeepCopyArray: %p", trueDeepCopyArray);

    //  array      
    [[array objectAtIndex:0] appendString:@" you"];

    //   deepCopyArray        
    NSLog(@"array[0]: %@", array[0]);
    NSLog(@"arrayCopy[0]: %@", deepCopyArray[0]);
    //   trueDeepCopyArray        ，          
    NSLog(@"arrayMutableCopy[0]: %@", trueDeepCopyArray[0]);
}

@interface Person : NSObject <NSCopying, NSMutableCopying>
/**  */
@property (nonatomic, copy) NSMutableString *name;
/**  */
@property (nonatomic, copy) NSString *address;
/**  */
@property (nonatomic, assign) NSInteger age;
@end

- (instancetype)init
{
    if (self = [super init])
    {
        self.name = [[NSMutableString alloc] initWithString:@"XiaoYaowang"];
        self.address = @"    ";
        self.age = 3;
    }
    return self;
}

- (id)copyWithZone:(NSZone *)zone
{
    Person *p = [[[self class] allocWithZone:zone] init];
    p.name = [self.name copy];
    p.address = [self.address copy];
    p.age =  self.age;

    return p;
}

- (id)mutableCopyWithZone:(NSZone *)zone
{
    Person *p = [[[self class] allocWithZone:zone] init];
    //  ，   mutableCopy  
    p.name = [self.name mutableCopy];
    p.address = [self.address copy];
    p.age =  self.age;

    return p;
}