解析后的SBJson Execptions(__ NSArrayM objectForKey :)

Question

我尝试使用SBJson解析Json时遇到了一些问题,我做了一些研究而且找不到有用的东西......

我跟着一些关于如何做的博客,但我仍然得到了这个错误:"__ NSArrayM objectForKey:"

所以这是我试图解析的Json:

{
"result": [
    {
        "authors": [
            "Eric Ries"
        ],
        "bc": 9780671607,
        "title": "Yeah",
        "urlImage": "www.yeah.hey",
        "description": "Hey..."
    }
    ]
}

这是我正在使用的代码:

SBJsonParser *json;
NSDictionary *jsonResults;
NSError *jsonError;

json = [ SBJsonParser new ];

// Get result in a NSDictionary
jsonResults = (NSDictionary*) [ json objectWithString:output error:&jsonError ];

// Check if there is an error
if (jsonResults == nil) {
    NSLog(@"Erreur lors de la lecture du code JSON (%@).", [ jsonError localizedDescription ]);  
} else {
    NSDictionary *book = (NSDictionary *)[ jsonResults objectForKey:@"result"];
    NSArray *items = (NSArray *) [book objectForKey:@"title"];
}

错误 :

-[__NSArrayM objectForKey:]: unrecognized selector sent to instance 0x7a2d390
2012-11-19 20:32:36.336 FMS[500:11f03] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayM objectForKey:]: unrecognized selector sent to instance 0x7a2d390'
*** First throw call stack:
(0x2245012 0x16a3e7e 0x22d04bd 0x2234bbc 0x223494e 0x8c6a 0x36093 0xb39e83 0x2204376 0x2203e06 0x21eba82 0x21eaf44 0x21eae1b 0x219f7e3 0x219f668 0x8365c 0x2d6d 0x2c95)
libc++abi.dylib: terminate called throwing an exception
Current language:  auto; currently objective-c

并通过使用objectForKey的valueForKey intead

[book valueForKey:@"title"];

我明白了:

(
    "Yeah"
)

而不只是呀

而且我不想再解析("是的")至少得到呀......

Answer 1

你得到那个错误,因为"book"是一个数组,而不是一个字典.如果所有结果看起来都像这样,那么"book"中只有一个外部对象.您只需将行定义书更改为:

NSDictionary *book = [[ jsonResults objectForKey:@"result"] lastObject];