使用 Mantle 解析 iOS 中的嵌套 json

Question

我正在尝试使用框架Mantle解析从服务接收的数据。json 有嵌套数据，我在解析它时遇到问题。json 如下所示：

  {
  "sections": [
    {
      "title": "title1",
      "level": 1,
      "content": [
        {
          "type": "type1",
          "text": "text1"
        }
      ],
      "images": []
    },
    {
      "title": "title2",
      "level": 2,
      "content": [
        {
          "type": "type2",
          "text": "text2"
        },
        {
          "type": "type9",
          "text": "text9"
        },
        {
          "type": "type4",
          "text": "text4"
        },
        {
          "type": "type6",
          "text": "text6"
        }
      ],
      "images": [
        {
          "src": "http://cvbcvcv",
          "caption": "caption"
        }
      ]
    }]
}

我使用的类是：

// MainObject.h
@interface MainObject : MTLModel <MTLJSONSerializing>
@property (strong, nonatomic) NSArray *sectionsArray;
+ (NSValueTransformer *)sectionsArrayJSONTransformer;
@end

@interface Section : MTLModel <MTLJSONSerializing>
@property (strong, nonatomic) NSString *title;
@property (assign, nonatomic) NSString *level;
@property (strong, nonatomic) NSArray *content;
@property (strong, nonatomic) NSArray *images;
+ (NSValueTransformer *)contentJSONTransformer;
+ (NSValueTransformer *)imagesJSONTransformer;
@end

@interface Content : MTLModel <MTLJSONSerializing>
@property (strong, nonatomic) NSString *type;
@property (strong, nonatomic) NSString *text;
@end

@interface Image : MTLModel <MTLJSONSerializing>
@property (strong, nonatomic) NSString *src;
@property (strong, nonatomic) NSString *caption;
@end

和

//MainObject.m
@implementation MainObject
+ (NSDictionary *)JSONKeyPathsByPropertyKey
{
    return @{
             @"sectionsArray" : @"sections",};
}
+ (NSValueTransformer *)sectionsArrayJSONTransformer
{
    return [MTLJSONAdapter dictionaryTransformerWithModelClass:[Section class]];
}
@end

@implementation Section
+ (NSDictionary *)JSONKeyPathsByPropertyKey
{
    return @{
             @"title" : @"title",
             @"level" : @"level",
             @"content" : @"content",
             @"images" : @"images",};
}
+ (NSValueTransformer *)contentJSONTransformer
{    
    return [MTLJSONAdapter arrayTransformerWithModelClass:[Content class]];
}
+ (NSValueTransformer *)imagesJSONTransformer
{
    return [MTLJSONAdapter arrayTransformerWithModelClass:[Image class]];
}
@end

@implementation Content
+ (NSDictionary *)JSONKeyPathsByPropertyKey
{
    return @{
             @"type" : @"type",
             @"text" : @"text",};
}
@end

@implementation Image
+ (NSDictionary *)JSONKeyPathsByPropertyKey
{
    return @{
             @"src" : @"src",
             @"caption" : @"caption",};
}
@end

然后，当我调用服务并尝试使用以下代码解析 json 时，响应对象从服务器获得的数据，数据显示为 nil：

for (NSArray *array in [responseObject valueForKey:@"sections"]) {
    NSArray *seccionArray = [MTLJSONAdapter modelsOfClass:[Section class] fromJSONArray:array error:nil];
}

我已经尝试了很多方法来很好地解析这些数据，但应用程序总是崩溃或返回 nil。我希望你能帮助我解决这个问题

Answer 1

为什么不能只使用一行NSJSONSerialization？

NSMutableDictionary *yourArray = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];

然后你从数组中获取你想要的东西...