ios - 字符0周围的值无效，NSJSONSerialization

我从服务器上获取了一个有效的响应:

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
    // Append the new data to the instance variable you declared


    //[_responseData appendData:data];

    NSString *responseBody = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    NSLog(@"%@",responseBody);

    if(data != NULL)
    {
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,
                                                 (unsigned long)NULL), ^(void) {

        NSError *error = nil;
        //NSMutableArray *jsonArray = [[CJSONDeserializer deserializer] deserializeAsArray:[responseBody dataUsingEncoding:NSUTF8StringEncoding] error:&error];
            NSMutableArray *jsonArray = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];
        if (error)
        {
            NSLog(@"JSONObjectWithData error: %@", error);
            [delegate onErrorGetArrayFromServer];
        }
        else
        [self parseJSON:jsonArray];

        });

    }
    else
    {
        if([delegate respondsToSelector:@selector(onErrorGetArrayFromServer)])
        {
            [delegate onErrorGetArrayFromServer];
        }
    }
}

响应就像:

[{
        "id": "37",
        "id_estado": "1",
        "id_categoria": "1",
        "nombre": "fer",
        "email": "[email protected]",
        "fecha": "2014-07-16 11:25:00",
        "observaciones": "as dasd asdasd sasd",
        "latitud": "37.619636",
        "longitud": "-4.318449",
        "foto": "images\/default.jpg"
    },

    {
        "id": "36",
        "id_estado": "1",
        "id_categoria": "6",
        "nombre": "Fernando",
        "email": "",
        "fecha": "2014-07-16 10:32:45",
        "observaciones": "que",
        "latitud": "37.6178690439634",
        "longitud": "-4.3238141387701",
        "foto": "images\/default.jpg"
    }
 ]

###它引发了错误:###

JSONObjectWithData error: Error Domain=NSCocoaErrorDomain Code=3840 "The operation couldn’t be completed. (Cocoa error 3840.)" (Invalid value around character 0.) UserInfo=0x9e0f610 {NSDebugDescription=Invalid value around character 0.}

我尝试了其他库( CJSON )，但抛出错误:

JSONObjectWithData error: Error Domain=kJSONScannerErrorDomain Code=-202 "Could not scan array. Could not scan a value." UserInfo=0xa15c0e0 {snippet=!HERE>![{"id":"37","id_esta, location=0, NSLocalizedDescription=Could not scan array. Could not scan a value., character=0, line=0}

我的服务器是REST服务器，对我的Android应用程序来说效果很好。

解决了
感谢@Himanshu Joshi:
为什么要解析didReceiveData:中的数据？数据没有完全下载到那里，您必须将数据附加到那里。解析connectionDidFinishLoading中的数据:委托(delegate)方法–
我解析了connectionDidFinishLoading:中的数据，一切正常。

最佳答案

我遇到了同样的问题，但这是因为我的初始URL不正确。

在解析JSON之前，需要检查响应。可能是在告诉您找不到它。

那时，数据实际上可以包含404 HTML页面。

我使用以下方法进行调试，并使用更简单的方法来处理Web请求:

// Asynchronous fetch the JSON and call the block when done
NSURLSessionDataTask *downloadTask =
[[NSURLSession sharedSession] dataTaskWithURL:url completionHandler:
^(NSData *data, NSURLResponse *response, NSError *error)
{
    NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *) response;

    if ([httpResponse statusCode]!=200)
    {
        // log [response  description]
        // log [NSString stringWithUTF8String:[data bytes]]
        return;
    }

    NSDictionary* jsonDic =
        [NSJSONSerialization JSONObjectWithData:data
                             options:NSJSONReadingAllowFragments
                             error:&error];

    if (!jsonDic)
    {
        return;
    }
    // process the JSON
}];
[downloadTask resume];