使用无效键值访问JArray值：“fields”。预期数组位置索引

I am using the guardian API to try and retrieve stories but keep receiving an exception. The string of json contains the below json, however I can't access the body using LINQ.

我正在使用监护人API来尝试和检索故事但仍然收到异常。 json的字符串包含下面的json,但是我无法使用LINQ访问正文。

Here it is:

这里是:

{
    "response":{
    "status":"ok",
    "userTier":"approved",
    "total":1,
    "startIndex":1,
    "pageSize":10,
    "currentPage":1,
    "pages":1,
    "orderBy":"newest",
    "results":[{
      "id":"sustainable-business/sustainable-finance-where-next-open-thread",
      "sectionId":"sustainable-business",
      "sectionName":"Guardian Sustainable Business",
      "webPublicationDate":"2014-02-13T13:27:00Z",
      "webTitle":"Where next for sustainable finance? - open thread",
      "webUrl":"http://www.theguardian.com/sustainable-business/sustainable-finance-where-next-open-thread",
      "apiUrl":"http://content.guardianapis.com/sustainable-business/sustainable-finance-where-next-open-thread",
      "fields":{
        "body":"<img src=\"http://hits.theguardian.com/b/ss/guardiangu-api/1/H.20.3/98867?ns=guardian&amp;pageName=Where+next+for+sustainable+finance%3F+-+open+thread+Article+2043222&amp;ch=Guardian+Sustainable+Business&amp;c2=461773&amp;c4=MIC%3A+Finance+%28GSB%29%2CMIC%3A+Guardian+Sustainable+Business%2CPRO%3A+Sustainability+%28Guardian+Professional%29&amp;c3=theguardian.com&amp;c6=Laura+Paddison&amp;c7=14-Feb-13&amp;c8=2043222&amp;c9=Article\" width=\"1\" height=\"1\" />..."
      }
     }]
     }
}

I have tried every thing including this:

我尝试过包括这个在内的所有事情:

string story = (string)ja["response"]["results"]["fields"]["body"];

Update:

public partial class Story : PhoneApplicationPage
{
    string url;
    string jsonData;

    // Http used so the json can be retrived via the get async methods
    HttpClient webClient = new HttpClient();

    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
        if (NavigationContext.QueryString.ContainsKey("key"))
        {
            string encodedValue = NavigationContext.QueryString["key"];
            url = Uri.UnescapeDataString(encodedValue);
            textBox.Text = url;
            guardianPanorama();
        }
    }
    private async void guardianPanorama()
    {
        try
        {
            HttpResponseMessage Result = await webClient.GetAsync(url);

            // This takes the http response content and is turned into a string
            jsonData = await Result.Content.ReadAsStringAsync();

            JObject ja = JObject.Parse(jsonData);

            // This takes the current bitcoin price and formats it so there is the      correct amount of decimal places
            string story = (string)ja["response"]["results"]["fields"]["body"];

            // It then gets added to the textbox
            textBox.Text = story;
        }
        catch (Exception errors)
        {
            MessageBox.Show("There has been a error with the Guardian API");
            Console.WriteLine("An error occured:" + errors);
        }
    }
}

Exception:

System.ArgumentException: Accessed JArray values with invalid key value: "fields". Array position index expected.

System.ArgumentException:使用无效键值访问JArray值:“fields”。预期数组位置索引。

at Newtonsoft.Json.Linq.JArray.get_Item(Object key)

at Newtonsoft.Json.Linq.JArray.get_Item(Object key)

1 个解决方案

#1

If you replace

如果你更换

// This takes the current bitcoin price and formats it so there is the correct amount of decimal places
string story = (string)ja["response"]["results"]["fields"]["body"];

with

// This takes the current bitcoin price and formats it so there is the correct amount of decimal places
string story = (string)ja["response"]["results"][0]["fields"]["body"];

that should work for your example. Note the square bracket after results in the example you provided, that indicates an array that should be accounted for in your access code.

这应该适用于你的例子。请注意在您提供的示例中得到的方括号,表示应在访问代码中考虑的数组。

#1