Question

在解析为NSDictionary后，我的Swift代码中收到了以下JSON。在我的函数中，我试图在＆＃34;结果＆＃34;中提取JSON对象。阻止为NSDIctionary []，但这会引发运行时错误。我不明白为什么，因为这是几天前的工作。

{
"results": [
    {
        "id": "3",
        "name": "The National",
        "slug": "thenational",
        "facebook_url": "https://www.facebook.com/thenationalofficial/",
        "twitter_url": "https://twitter.com/The_National",
        "profile_image": "http://example.staging.com/media/profile_image/thumbnail_263x263/1352756032.jpg",
        "_type": "artist",
        "resource_uris": {
        }
    },
    {
        "id": "5",
        "name": "Mayer Hawthorne",
        "slug": "mayerhawthorne",
        "facebook_url": "https://www.facebook.com/MayerHawthorne",
        "twitter_url": "https://twitter.com/MayerHawthorne",
        "profile_image": "http://example.example.com/media/profile_image/thumbnail_263x263/1352755133.png",
        "_type": "artist",
        "resource_uris": {
        }
    },
    {
        "id": "20",
        "name": "I Play Maracas",
        "slug": "iplaymaracas",
        "facebook_url": "",
        "twitter_url": "",
        "profile_image": "http://staging.wedemand.com/images/en/img-list-home.gif",
        "_type": "artist",
        "resource_uris": {
            "_demanded_by": null,
            "demand_url": "http://ec2-54-86-17-163.compute-1.amazonaws.com/artists/20/?demand=1&access_token={}",
            "dismiss_url": "http://ec2-54-86-17-163.compute-1.amazonaws.com/artists/20/?demand=0&access_token={}"
        }
    },
    {
        "id": "35",
        "name": "Black SuperHeros",
        "slug": "blacksuperheros",
        "facebook_url": "",
        "twitter_url": "",
        "profile_image": "http://staging.example.com/images/en/img-list-home.gif",
        "_type": "artist",
        "resource_uris": {
        }
    },
    {
        "id": "49",
        "name": "Ayman Elgadi",
        "slug": "aymanelgadi",
        "facebook_url": "",
        "twitter_url": "",
        "profile_image": "http://staging.example.com/images/en/img-list-home.gif",
        "_type": "artist",
        "resource_uris": {
        }
    },
    {
        "id": "8874",
        "name": "Lauri",
        "slug": "lauri",
        "facebook_url": "http://www.facebook.com/hughlaurieblues",
        "twitter_url": "http://twitter.com/hughlaurieblues",
        "profile_image": "http://staging.example.com/media/profile_image/thumbnail_263x263/lauri_profilepic.jpg",
        "_type": "artist",
        "resource_uris": {
        }
    }
]
}

我的IOS-Swift代码在被AFNetworking lib解析后接收到NSDictionary对象，并传递给将结果数组转换为NSDictionary []的函数，现在正在抛出运行时错误，而早些时候它正在运行。

(operation: AFHTTPRequestOperation!, responseObject: AnyObject!) in println("JSON: " + responseObject.description)

var jsonResult: NSDictionary = responseObject as NSDictionary

将此jsonResult传递给下面的函数，该函数尝试转换为NSDictionary []

let allResults: NSDictionary[] = results["results"] as NSDictionary[]

更新：我打印结果对象的类，因为它返回__NSCFDictionary。

这里What is an NSCFDictionary?是关于这个问题的讨论，并说就像NSDictionary一样使用它，但在我看来它不起作用。

Answer 1

results的值不是JSON中的字典，而是数组。你应该得到这样的东西;

let allResults: NSArray = results["results"] as NSArray

由于NSDictionary []抛出EXC_BAD_INSTRUCTION运行时错误，因此从JSON结果进行数据转换

1 个答案: