Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

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

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.

Here it is:

{
    "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:

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.

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

like image 301
user3317526 Avatar asked Feb 17 '14 03:02

user3317526


1 Answers

If you replace

// 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.

like image 65
Andrew Savinykh Avatar answered Sep 23 '22 20:09

Andrew Savinykh