I am using Alpha Vantage API to try and pull daily stock info. I am really new to using APIs and don't know what I am doing wrong

Issue

So I am using c# xamarin and making a basic stock app that can pull stock quotes using the Alpha Vantage API. I have what I thought might work but it isn't working at all. Yes this is a school project so I don't expect people to just do it. The purpose of this app is to use the API and I need to show the data that it provides after the user enters in a stock symbol from the first page of the app. I need to send that symbol with the api and I am not sure I am pulling in JSON object and I don't know how to get to each field in the object when I do retrieve the JSON correctly.This code is what im trying and I am not getting any information populated into any of my textViews.

namespace Stock_Quote
{
    [Activity(Label = "StockInfoActivity1")]
    public class StockInfoActivity1 : Activity
    {
        private ISharedPreferences prefs = Application.Context.GetSharedPreferences("APP_DATA", FileCreationMode.Private);
        TextView txtSymbol, txtOpen, txtClose, txtHigh, txtLow, txtVolume;
        string webservice_url = "https://www.alphavantage.co/query?function=TIME_SERIES_DAILY&symbol=";

        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);

            // Create your application here
            SetContentView(Resource.Layout.activity_stock_info);
            txtSymbol = FindViewById<TextView>(Resource.Id.txtSymbol);
            txtOpen = FindViewById<TextView>(Resource.Id.txtOpen);
            txtClose = FindViewById<TextView>(Resource.Id.txtClose);
            txtHigh = FindViewById<TextView>(Resource.Id.txtHigh);
            txtLow = FindViewById<TextView>(Resource.Id.txtLow);
            txtVolume = FindViewById<TextView>(Resource.Id.txtVolume);
            string current = prefs.GetString("current", "no stok symbol found");

            //txtSymbol.Text = current;

            try
            {
                webservice_url = webservice_url + current + "&apikey=AVALIDAPIKEY";
                Uri url = new Uri(webservice_url);
                var webRequest = WebRequest.Create(url);

                if (webRequest != null)
                {

                    webRequest.Method = "GET";
                    webRequest.ContentType = "application/json";

                    //Get the response 
                    WebResponse wr = webRequest.GetResponseAsync().Result;
                    Stream receiveStream = wr.GetResponseStream();
                    StreamReader reader = new StreamReader(receiveStream);

                    Stock currentStockInfo = JsonConvert.DeserializeObject<Stock>(reader.ReadToEnd());

                    if (currentStockInfo.RestResponse.result == null)
                    {
                        txtSymbol.Text = "No stock found";
                    }
                    else
                    {                        
                        txtSymbol.Text = current;
                        txtOpen.Text = currentStockInfo.RestResponse.stockInfo.Open;
                        txtClose.Text = currentStockInfo.RestResponse.stockInfo.Close;
                        txtHigh.Text = currentStockInfo.RestResponse.stockInfo.High;
                        txtLow.Text = currentStockInfo.RestResponse.stockInfo.Low;
                        txtVolume.Text = currentStockInfo.RestResponse.stockInfo.Volume;
                    }


                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
        }
    }
    public class Result
    {
        public string Information { get; set; }
        public string Symbol { get; set; }
        public string Last { get; set; }
        public string Size { get; set; }
        public string TimeZone { get; set; }
    }

    public class StockInfo
    {
        public string Open { get; set; }
        public string High { get; set; }
        public string Low { get; set; }
        public string Close { get; set; }
        public string Volume { get; set; }
    }

    public class RestResponse
    {       
        public Result result { get; set; }
        public StockInfo stockInfo { get; set; }
    }

    public class Stock
    {
        public RestResponse RestResponse { get; set; }
    }
}

Solution

The JSON that's being returned from that endpoint doesn't quite match your model.

Here's the line where you tell your program how to parse the response:

Stock currentStockInfo = JsonConvert.DeserializeObject(reader.ReadToEnd());

...but the response looks like this:

{
    "Meta Data": {
        "1. Information": "Daily Prices (open, high, low, close) and Volumes",
        "2. Symbol": "MSFT",
        "3. Last Refreshed": "2018-12-10 16:00:02",
        "4. Output Size": "Compact",
        "5. Time Zone": "US/Eastern"
    },
    "Time Series (Daily)": {
        "2018-12-10": {
            "1. open": "104.8000",
            "2. high": "107.9800",
            "3. low": "103.8900",
            "4. close": "107.5900",
            "5. volume": "39050766"
        },
        "2018-12-07": {
            "1. open": "108.3800",
            "2. high": "109.4500",
            "3. low": "104.3000",
            "4. close": "104.8200",
            "5. volume": "45044937"
        }...
    ...
    ...
    ...

}

You're trying to turn this entire response into one Stock object, which isn't going to work. The response isn't a Stock, it's a response with 2 objects, one of which has a lot of Stock objects.

You could try to create a model for this*, but I'd recommend turning this entire response into a JObject (another object in NewtonSoft JSON.Net).

Here's a DotNetFiddle I put together to demonstrate how it works.

https://dotnetfiddle.net/Iz8UsD

Let me know if I can add anything more helpful.

EDIT: * You can probably get a strongly typed model to work here,the trouble is that each Stock has a different JSON name. I don't know how to get the parser to parse each as a Stock while still keeping the data around. I'll have to play with that tonight.

Answered By - Joe Cullinan