ios - 无法从 JSON 流中检索对象以进行枚举

Question

我试图掌握如何在 Objective C 中使用 block 。在我编写的这个简单的应用程序中，我获得了一组图像作为 JSON 流。我正在尝试取出图像并将它们对象化，然后将它们收集到 NSMutableArray 中。下面是我的代码

WebImage.h

#import <Foundation/Foundation.h>

@interface WebImage : NSObject <NSCopying>

@property (strong, nonatomic) NSString *imageId;
@property (strong, nonatomic) NSString *imageName;
@property (strong, nonatomic) NSString *imagePath;

- (id)initWithId:(NSString *)imageId andName:(NSString *)imageName andPath:(NSString *)imagePath;
+ (NSArray *)retrieveAllImages;

@end

WebImage.m

#import "WebImage.h"
#import "AFNetworking.h"

#define HOST_URL @"http://toonmoodz.osmium.lk/"

@implementation WebImage

#pragma mark - NSCopying
- (id)copyWithZone:(NSZone *)zone
{
    WebImage *newImage = [WebImage new];
    newImage.imageId = self.imageId;
    newImage.imageName = self.imageName;
    newImage.imagePath = self.imagePath;

    return newImage;
}

- (id)initWithId:(NSString *)imageId andName:(NSString *)imageName andPath:(NSString *)imagePath
{
    if (self = [self init]) {
        self.imageId = imageId;
        self.imageName = imageName;
        self.imagePath = imagePath;
    }
    return self;
}

+ (NSArray *)retrieveAllImages  
{
    NSMutableArray *images = [[NSMutableArray alloc] init];

    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
    [manager GET:[NSString stringWithFormat:@"%@%@", HOST_URL, @"All_Images.php"] parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {

        NSDictionary *dict = responseObject[@"Images"];
        NSArray *arr = [dict allValues];
        [arr enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
            NSDictionary *image = obj;
            NSLog(@"%@", image);
            [images addObject:[[WebImage alloc] initWithId:[image objectForKey:@"id"]
                                                         andName:[image objectForKey:@"name"]
                                                         andPath:[image objectForKey:@"image"]]];
        }];

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Error in image retrieveing: %@", error.localizedDescription);
    }];

    return [images copy];
}

传入的 JSON 流如下所示

{
    Images =  (
        {
            createddate = "2014-01-08 12:20:24";
            id = 1;
            image = "images/Rock_1.png";
            isEnabled = 1;
            name = "Rock_1";
        },
        {
            createddate = "2014-01-08 15:12:26";
            id = 2;
            image = "images/Rock_2.png";
            isEnabled = 1;
            name = "Rock_2";
        }
    );
}

我的问题是我无法从 JSON 字符串中检索图像对象。当我调试时，编译器甚至没有进入 retrieveAllImages 方法中的 GET block ，而是直接跳转到 return 语句。

谁能告诉我如何纠正这个问题？

我创建了一个项目来展示我面临的问题并上传了它 here如果你想快速浏览一下。

谢谢。

Answer 1

问题在于

NSDictionary *dict = responseObject[@"Images"];NSArray *arr = [dict allValues];

responseObject[@"图片"];返回一个 NSArray 类。因此，将您的命令更改为 NSArray 类。并枚举那个“dict”对象。你不需要你的对象。