将 NSMutableDictionary 添加到数组中以进行按钮操作

Question

我有一个 NSMutableDictionary：

sampleDict = [NSMutableDictionary new];

[sampleDict setObject:@"FooIndex" forKey:@"Key_1"]; // adds @"Foo"
[sampleDict setObject:@"FooOne" forKey:@"Key_2"]; // adds @"Foo"
[sampleDict setObject:@"FooTwo" forKey:@"Key_3"]; // adds @"Foo"
[sampleDict setObject:@"FoFour" forKey:@"Key_4"]; // adds @"Foo"
[sampleDict setObject:@"FooFivve" forKey:@"Key_5"]; // adds @"Foo"

我想将此字典添加到 Array on Button 操作这里的代码是这样的，

arraytesting = [NSMutableArray new];

- (IBAction)action:(id)sender {
    [arraytesting addObject:sampleDict];
    NSLog(@"Sample arraytesting>>>>> %@",arraytesting);

}

最后的输出是：

(
        {
        "Key_1" = FooIndex;
        "Key_2" = FooOne;
        "Key_3" = FooTwo;
        "Key_4" = FoFour;
        "Key_5" = FooFivve;
    }
)

但是当我需要更新字典时：

[sampleDict setObject:@"one" forKey:@"Key_1"]; // adds @"Foo"
[sampleDict setObject:@"two" forKey:@"Key_2"]; // adds @"Foo"
[sampleDict setObject:@"three" forKey:@"Key_3"]; // adds @"Foo"
[sampleDict setObject:@"FoFour" forKey:@"Key_4"]; // adds @"Foo"
[sampleDict setObject:@"FooFivve" forKey:@"Key_5"]; // adds @"Foo"

输出如下：

(
    {
        "Key_1" = FooIndex;
        "Key_2" = FooOne;
        "Key_3" = FooTwo;
        "Key_4" = FoFour;
        "Key_5" = FooFivve;
    },
    {
        "Key_1" = FooIndex;
        "Key_2" = FooOne;
        "Key_3" = FooTwo;
        "Key_4" = FoFour;
        "Key_5" = FooFivve;
    }
)

我希望输出是这样的：

(
    {
        "Key_1" = FooIndex;
        "Key_2" = FooOne;
        "Key_3" = FooTwo;
        "Key_4" = FoFour;
        "Key_5" = FooFivve;
    },
    {
        "Key_1" = one;
        "Key_2" = two;
        "Key_3" = three;
        "Key_4" = FoFour;
        "Key_5" = FooFivve;
    }
)

Answer 1

向数组添加对对象的引用。之后，您编辑您的字典并再次添加它的引用。您可以调用copy 来创建sampleDict 的新实例。 你的方法必须是这样的：

- (IBAction)action:(id)sender { [arraytesting addObject:[sampleDict copy]]; NSLog(@"Sample arraytesting>>>>> %@",arraytesting); }

Answer 2

[sampleDict setObject:@"one" forKey:@"Key_1"]; // adds @"Foo"
[sampleDict setObject:@"two" forKey:@"Key_2"]; // adds @"Foo"
[sampleDict setObject:@"three" forKey:@"Key_3"]; // adds @"Foo"
[sampleDict setObject:@"FoFour" forKey:@"Key_4"]; // adds @"Foo"
[sampleDict setObject:@"FooFivve" forKey:@"Key_5"]; // adds @"Foo"

在这里，您使用的是相同 sampleDict 的相同参考。而不是再次创建一个新对象并添加。

smapleDict = [NSMutableArray new]

[sampleDict setObject:@"one" forKey:@"Key_1"]; // adds @"Foo"
    [sampleDict setObject:@"two" forKey:@"Key_2"]; // adds @"Foo"
    [sampleDict setObject:@"three" forKey:@"Key_3"]; // adds @"Foo"
    [sampleDict setObject:@"FoFour" forKey:@"Key_4"]; // adds @"Foo"
    [sampleDict setObject:@"FooFivve" forKey:@"Key_5"]; // adds @"Foo"

Answer 3

您的字典sampleDict 是一个引用，因此您需要对其进行可变副本，如果您不修改原始字典，这将修改您数组上的所有字典，因此您需要复制、修改和添加然后到你的数组，像这样

#import "ViewController.h"

@interface ViewController ()
@property NSMutableArray * arrayTesting;
@property NSMutableDictionary * sampleDict;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.sampleDict = [NSMutableDictionary new];


    [self.sampleDict setObject:@"FooIndex" forKey:@"Key_1"]; // adds @"Foo"
    [self.sampleDict setObject:@"FooOne" forKey:@"Key_2"]; // adds @"Foo"
    [self.sampleDict setObject:@"FooTwo" forKey:@"Key_3"]; // adds @"Foo"
    [self.sampleDict setObject:@"FoFour" forKey:@"Key_4"]; // adds @"Foo"
    [self.sampleDict setObject:@"FooFivve" forKey:@"Key_5"]; // adds @"Foo"

    self.arrayTesting = [NSMutableArray new];

    [self.arrayTesting addObject:self.sampleDict];
    NSLog(@"Sample arraytesting>>>>> %@",self.arrayTesting);
}

- (IBAction)buttonAction:(id)sender {



    NSMutableDictionary * toModify = [self.sampleDict mutableCopy];

    [toModify setObject:@"One" forKey:@"Key_1"]; // adds @"Foo"
    [toModify setObject:@"Two" forKey:@"Key_2"]; // adds @"Foo"
    [toModify setObject:@"Three" forKey:@"Key_3"]; // adds @"Foo"
    [toModify setObject:@"FoFour" forKey:@"Key_4"]; // adds @"Foo"
    [toModify setObject:@"FooFivve" forKey:@"Key_5"]; // adds @"Foo"

    [self.arrayTesting addObject:toModify];
    NSLog(@"Sample arraytesting>>>>> %@",self.arrayTesting);
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


@end

希望对你有帮助