Ios 从AFN网络转换JSON

我使用AFNetworking从URL获取JSON，JSON被解析并被转换成NSData格式，然后再被放入数组中。然而，它似乎不起作用。我觉得我很愚蠢，因为它以前有效，但现在有效了-

-(void)loadFromServer{

        NSString *trendsURL = [NSString stringWithFormat:@"http://myurl.com/data.json"];

        NSURL *url = [NSURL URLWithString:trendsURL];
        NSURLRequest *request = [NSURLRequest requestWithURL:url];

        AFJSONRequestOperation *operation = [AFJSONRequestOperation
                                             JSONRequestOperationWithRequest:request
                                             success:^(NSURLRequest *request, NSHTTPURLResponse *response, id json) {
                                                 self.results = [json valueForKeyPath:@"data"];
                                             } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
                                             }];

        [operation start];




        NSError *anError = nil;
        NSArray *parsedElements = [NSJSONSerialization JSONObjectWithData:elementsData
                                                                  options:NSJSONReadingAllowFragments
                                                                    error:&anError];

        for (NSDictionary *aModuleDict in parsedElements){
            MosData *aMosModule = [[MosData alloc] initWithDictionary:aModuleDict];
            [elements addObject:aMosModule];
        }
    }

数据单独显示在类似集合的视图中，当我从文件而不是服务器访问数据时，此单独视图不会出现问题

-(void)loadFromDisk{
    NSString *pathString = [[NSBundle mainBundle] pathForResource:@"data" ofType:@"json"];
    NSData *elementsData = [NSData dataWithContentsOfFile:pathString];

    NSError *anError = nil;
    NSArray *parsedElements = [NSJSONSerialization JSONObjectWithData:elementsData
                                                              options:NSJSONReadingAllowFragments
                                                                error:&anError];

    for (NSDictionary *aModuleDict in parsedElements){
        MosData *aMosModule = [[MosData alloc] initWithDictionary:aModuleDict];
        [elements addObject:aMosModule];
    }
}

获取的JSON如下所示：

  {
    "imageLink": "http://link.com/image.jpg",
    "size": 1,
    "title": "Food"
  }

我又试了一次，但还是不起作用。结果是一个声明的NSArray

-(void)loadFromServer{

    NSString *trendsURL = [NSString stringWithFormat:@"http://url.com/data.json"];

    NSURL *url = [NSURL URLWithString:trendsURL];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];

    AFJSONRequestOperation *operation = [AFJSONRequestOperation
                                         JSONRequestOperationWithRequest:request
                                         success:^(NSURLRequest *request, NSHTTPURLResponse *response, id json) {
                                             NSLog(@"Custom Mosaic: %@", json);
                                            self.results = [json valueForKeyPath:@"data"];
                                         } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
                                         }];

    [operation start];



    for (NSDictionary *aModuleDict in self.results){
        MosData *aMosModule = [[MosData alloc] initWithDictionary:aModuleDict];
        [elements addObject:aMosModule];
    }
}

我认为问题实际上可能是，由于某种原因，它不会获取AFNetworking操作中解析的数据的结果

-(id)init{
    self = [super init];

    if (self){
        elements = [[NSMutableArray alloc] init];
        [self loadFromServer];
    }

    return self;
}

//  WWDC 2012 proposed method
+ (CustomMosDatasource *)sharedInstance {
    static CustomMosDatasource *sharedInstance;
    if (sharedInstance == nil)
        sharedInstance = [CustomMosDatasource new];
    return sharedInstance;
}

#pragma mark - MosViewDatasourceProtocol

-(NSArray *)mosElements{
    NSArray *retVal = elements;
    return retVal;
}

日志的结果就是JSON：

Custom Mosaic: {
    data =     (
                {
            imageFilename = "http://distilleryimage6.instagram.com/9969123a6af311e2b6c722000a9d0edd_7.jpg";
            size = 1;
            title = "Title";
        },

---

您的json似乎没有keyPath数据，请删除valueForKeyPath:@data，请粘贴NSLog@Custom马赛克：%@，你的问题中有json。 该操作是异步的。在请求返回数据后调用success块。请像这样将代码放入成功块

-(void)loadFromServer{

    NSString *trendsURL = [NSString stringWithFormat:@"http://url.com/data.json"];

    NSURL *url = [NSURL URLWithString:trendsURL];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];

    AFJSONRequestOperation *operation = [AFJSONRequestOperation
                                         JSONRequestOperationWithRequest:request
                                         success:^(NSURLRequest *request, NSHTTPURLResponse *response, id json) {
                                            NSLog(@"Custom Mosaic: %@", json);
                                            // your json doesn't have keyPath "data"
                                            self.results = json;
                                            // Codes moved into success block
                                            for (NSDictionary *aModuleDict in self.results){
                                                MosData *aMosModule = [[MosData alloc] initWithDictionary:aModuleDict];
                                                [elements addObject:aMosModule];
                                            }

                                         } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
                                         }];

    [operation start];
}

---

1什么不起作用？错误消息？预期和实际结果2元素数据来自哪里？您的代码中未设置或初始化它。-3 AFJSONRequestOperation异步工作！！抱歉，我添加了更多的细节，出现的问题是集合视图中没有显示任何内容。这是某种形式的解析错误，但我不知道是什么。你的实际代码是什么？在我看来，您缺少请求的异步方法。尝试在success回调下执行for语句。感谢您的回答，但这似乎也不起作用，我已经按照上面添加的方式再次尝试了。但是它真的不想工作。谢谢你的代码，但这似乎也不起作用，JSON是按照AFNetworking提取和正确解析的，它是forNSDictionary。。。这似乎是问题所在。结果如何NSLog@Custom马赛克：%@，我已将其添加到问题本身中。

-(void)loadFromServer{

    NSString *trendsURL = [NSString stringWithFormat:@"http://url.com/data.json"];

    NSURL *url = [NSURL URLWithString:trendsURL];
    NSURLRequest *request = [NSURLRequest requestWithURL:url];

    AFJSONRequestOperation *operation = [AFJSONRequestOperation
                                         JSONRequestOperationWithRequest:request
                                         success:^(NSURLRequest *request, NSHTTPURLResponse *response, id json) {
                                            NSLog(@"Custom Mosaic: %@", json);
                                            // your json doesn't have keyPath "data"
                                            self.results = json;
                                            // Codes moved into success block
                                            for (NSDictionary *aModuleDict in self.results){
                                                MosData *aMosModule = [[MosData alloc] initWithDictionary:aModuleDict];
                                                [elements addObject:aMosModule];
                                            }

                                         } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
                                         }];

    [operation start];
}