使用NewtonSoft解析JSON时出错

Question

Merry Christmas stackies! I'm trying to parse some JSON from the Wunderground weather API and I'm running into an issue when trying to assign values to variables. Here is a link to the JSON. Just know that the class structure I'm providing is a conglomerate in order to accommodate multiple JSON return file structures. I'll give the class structre, then the call from main, and finally the actual method with the error notated. I'm working in Xamarin, formerlly MonoDevelop. Thanks for anything you can come up with!

The error reads: Newtonsoft.Json.JsonReaderException has been thrown "Cannot convert String to Integer: 5.0 Path 'current_observation.wind_gust_mph', line 60, position 24.

public class Wunder
{

    //constructor
    public Wunder ()
    {

    }

    //JSON classes
    public class HistoryResponseContainer
    {
        public ResponseInfo response { get; set; }
        public HistoryInfo history { get; set; }
        public Location location { get; set; }
        public CurrentObservation current_observation { get; set; }
    }

    public class ResponseInfo
    {
        public string version { get; set; }
        public string termsofService { get; set; }
        public Dictionary<string, int> features { get; set; }
    }

    public class HistoryInfo
    {
        public WUDate date { get; set; }
        public WUDate utcdate { get; set; }
        public Observation[] observations { get; set; }
        public Dailysummary[] dailysummary { get; set; }
    }

    public class WUDate
    {
        public string pretty { get; set; }
        public string year { get; set; }
        public string mon { get; set; }
        public string mday { get; set; }
        public string hour { get; set; }
        public string min { get; set; }
        public string tzname { get; set; }

        public DateTime Value
        {
            get
            {
                int year = int.Parse(this.year);
                int month = int.Parse(this.mon);
                int day = int.Parse(this.mday);
                int hour = int.Parse(this.hour);
                int minute = int.Parse(this.min);

                var kind = this.tzname == "UTC"
                           ? DateTimeKind.Utc
                           : DateTimeKind.Unspecified;

                return new DateTime(year, month, day, hour, minute, 0, kind);
            }
        }
    }

    public class Observation
    {
        public WUDate date { get; set; }
        public WUDate utcdate { get; set; }
        public string tempm { get; set; }
        public string tempi { get; set; }
        public string dewptm { get; set; }
        public string dewpti { get; set; }
        public string hum { get; set; }
        public string wspdm { get; set; }
        public string wspdi { get; set; }
        public string wgustm { get; set; }
        public string wgusti { get; set; }
        public string wdird { get; set; }
        public string wdire { get; set; }
        public string vism { get; set; }
        public string visi { get; set; }
        public string pressurem { get; set; }
        public string pressurei { get; set; }
        public string windchillm { get; set; }
        public string windchilli { get; set; }
        public string heatindexm { get; set; }
        public string heatindexi { get; set; }
        public string precipm { get; set; }
        public string precipi { get; set; }
        public string conds { get; set; }
        public string icon { get; set; }
        public string fog { get; set; }
        public string rain { get; set; }
        public string snow { get; set; }
        public string hail { get; set; }
        public string thunder { get; set; }
        public string tornado { get; set; }
        public string metar { get; set; }
    }

    public class Dailysummary
    {
        public WUDate date { get; set; }
        public string fog { get; set; }
        public string rain { get; set; }
        public string snow { get; set; }
        public string snowfallm { get; set; }
        public string snowfalli { get; set; }
        public string monthtodatesnowfallm { get; set; }
        public string monthtodatesnowfalli { get; set; }
        public string since1julsnowfallm { get; set; }
        public string since1julsnowfalli { get; set; }
        public string snowdepthm { get; set; }
        public string snowdepthi { get; set; }
        public string hail { get; set; }
        public string thunder { get; set; }
        public string tornado { get; set; }
        public string meantempm { get; set; }
        public string meantempi { get; set; }
        public string meandewptm { get; set; }
        public string meandewpti { get; set; }
        public string meanpressurem { get; set; }
        public string meanpressurei { get; set; }
        public string meanwindspdm { get; set; }
        public string meanwindspdi { get; set; }
        public string meanwdire { get; set; }
        public string meanwdird { get; set; }
        public string meanvism { get; set; }
        public string meanvisi { get; set; }
        public string humidity { get; set; }
        public string maxtempm { get; set; }
        public string maxtempi { get; set; }
        public string mintempm { get; set; }
        public string mintempi { get; set; }
        public string maxhumidity { get; set; }
        public string minhumidity { get; set; }
        public string maxdewptm { get; set; }
        public string maxdewpti { get; set; }
        public string mindewptm { get; set; }
        public string mindewpti { get; set; }
        public string maxpressurem { get; set; }
        public string maxpressurei { get; set; }
        public string minpressurem { get; set; }
        public string minpressurei { get; set; }
        public string maxwspdm { get; set; }
        public string maxwspdi { get; set; }
        public string minwspdm { get; set; }
        public string minwspdi { get; set; }
        public string maxvism { get; set; }
        public string maxvisi { get; set; }
        public string minvism { get; set; }
        public string minvisi { get; set; }
        public string gdegreedays { get; set; }
        public string heatingdegreedays { get; set; }
        public string coolingdegreedays { get; set; }
        public string precipm { get; set; }
        public string precipi { get; set; }
        public string precipsource { get; set; }
        public string heatingdegreedaysnormal { get; set; }
        public string monthtodateheatingdegreedays { get; set; }
        public string monthtodateheatingdegreedaysnormal { get; set; }
        public string since1sepheatingdegreedays { get; set; }
        public string since1sepheatingdegreedaysnormal { get; set; }
        public string since1julheatingdegreedays { get; set; }
        public string since1julheatingdegreedaysnormal { get; set; }
        public string coolingdegreedaysnormal { get; set; }
        public string monthtodatecoolingdegreedays { get; set; }
        public string monthtodatecoolingdegreedaysnormal { get; set; }
        public string since1sepcoolingdegreedays { get; set; }
        public string since1sepcoolingdegreedaysnormal { get; set; }
        public string since1jancoolingdegreedays { get; set; }
        public string since1jancoolingdegreedaysnormal { get; set; }
    }

    public class Station
    {
        public string city { get; set; }
        public string state { get; set; }
        public string country { get; set; }
        public string icao { get; set; }
        public string lat { get; set; }
        public string lon { get; set; }
    }

    public class Airport
    {
        public List<Station> station { get; set; }
    }

    public class Station2
    {
        public string neighborhood { get; set; }
        public string city { get; set; }
        public string state { get; set; }
        public string country { get; set; }
        public string id { get; set; }
        public double lat { get; set; }
        public double lon { get; set; }
        public int distance_km { get; set; }
        public int distance_mi { get; set; }
    }

    public class Pws
    {
        public List<Station2> station { get; set; }
    }

    public class NearbyWeatherStations
    {
        public Airport airport { get; set; }
        public Pws pws { get; set; }
    }

    public class Location
    {
        public string type { get; set; }
        public string country { get; set; }
        public string country_iso3166 { get; set; }
        public string country_name { get; set; }
        public string state { get; set; }
        public string city { get; set; }
        public string tz_short { get; set; }
        public string tz_long { get; set; }
        public string lat { get; set; }
        public string lon { get; set; }
        public string zip { get; set; }
        public string magic { get; set; }
        public string wmo { get; set; }
        public string l { get; set; }
        public string requesturl { get; set; }
        public string wuiurl { get; set; }
        public NearbyWeatherStations nearby_weather_stations { get; set; }
    }

    public class CurrentObservation
    {
        public Image image { get; set; }
        public DisplayLocation display_location { get; set; }
        public ObservationLocation observation_location { get; set; }
        public Estimated estimated { get; set; }
        public string station_id { get; set; }
        public string observation_time { get; set; }
        public string observation_time_rfc822 { get; set; }
        public string observation_epoch { get; set; }
        public string local_time_rfc822 { get; set; }
        public string local_epoch { get; set; }
        public string local_tz_short { get; set; }
        public string local_tz_long { get; set; }
        public string local_tz_offset { get; set; }
        public string weather { get; set; }
        public string temperature_string { get; set; }
        public double temp_f { get; set; }
        public double temp_c { get; set; }
        public string relative_humidity { get; set; }
        public string wind_string { get; set; }
        public string wind_dir { get; set; }
        public int wind_degrees { get; set; }
        public double wind_mph { get; set; }
        public int wind_gust_mph { get; set; }
        public int wind_kph { get; set; }
        public int wind_gust_kph { get; set; }
        public string pressure_mb { get; set; }
        public string pressure_in { get; set; }
        public string pressure_trend { get; set; }
        public string dewpoint_string { get; set; }
        public int dewpoint_f { get; set; }
        public int dewpoint_c { get; set; }
        public string heat_index_string { get; set; }
        public string heat_index_f { get; set; }
        public string heat_index_c { get; set; }
        public string windchill_string { get; set; }
        public string windchill_f { get; set; }
        public string windchill_c { get; set; }
        public string feelslike_string { get; set; }
        public string feelslike_f { get; set; }
        public string feelslike_c { get; set; }
        public string visibility_mi { get; set; }
        public string visibility_km { get; set; }
        public string solarradiation { get; set; }
        public string UV { get; set; }
        public string precip_1hr_string { get; set; }
        public string precip_1hr_in { get; set; }
        public string precip_1hr_metric { get; set; }
        public string precip_today_string { get; set; }
        public string precip_today_in { get; set; }
        public string precip_today_metric { get; set; }
        public string icon { get; set; }
        public string icon_url { get; set; }
        public string forecast_url { get; set; }
        public string history_url { get; set; }
        public string ob_url { get; set; }
    }

    public class ObservationLocation
    {
        public string full { get; set; }
        public string city { get; set; }
        public string state { get; set; }
        public string country { get; set; }
        public string country_iso3166 { get; set; }
        public string latitude { get; set; }
        public string longitude { get; set; }
        public string elevation { get; set; }
    }

    public class Image
    {
        public string url { get; set; }
        public string title { get; set; }
        public string link { get; set; }
    }

    public class DisplayLocation
    {
        public string full { get; set; }
        public string city { get; set; }
        public string state { get; set; }
        public string state_name { get; set; }
        public string country { get; set; }
        public string country_iso3166 { get; set; }
        public string zip { get; set; }
        public string magic { get; set; }
        public string wmo { get; set; }
        public string latitude { get; set; }
        public string longitude { get; set; }
        public string elevation { get; set; }
    }

    public class Estimated
    {
    }

And here is the call from main.

class MainClass
{
    public static void Main (string[] args)
    {

        Wunder data = new Wunder ();
        string StationID = "KCOBOULD67";

        string CurrentConditions = data.GetCurrentConditions (StationID);

        Console.WriteLine (CurrentConditions); 

    }

}

Lastly, this is the method being called. I took out my Wunderground Key. If you want an example of the return JSON, check the link at the top.

    public String GetCurrentConditions(string StationID){

        String url = @"http://api.wunderground.com/api/" + wundergroundkey + "/conditions/q/pws:" + StationID + ".json";
        Uri uri = new Uri(url);
        WebRequest webRequest = WebRequest.Create(uri);
        WebResponse response = webRequest.GetResponse();
        StreamReader streamReader = new StreamReader(response.GetResponseStream());
        String responseData = streamReader.ReadToEnd();

        var container = JsonConvert.DeserializeObject<HistoryResponseContainer> (responseData);

        String stationid = container.current_observation.station_id;
        String station_lat = container.current_observation.observation_location.latitude;
        String station_lon = container.current_observation.observation_location.longitude;

        String station_data = stationid + station_lat + station_lon;

        return (station_data);

    } //End GetCurrentConditions

Again, the error reads: Newtonsoft.Json.JsonReaderException has been thrown "Cannot convert String to Integer: 5.0 Path 'current_observation.wind_gust_mph', line 60, position 24.

Answer 1

You provided us a link to the following JSON:

http://api.wunderground.com/api/21fd5aec70326254/conditions/q/CA/San_Francisco.json

As you see there, the property wind_gust_mph is 0 (without the quotes, so an Integer). This JSON also works very well. But in your code you use the following JSON:

http://api.wunderground.com/api/21fd5aec70326254/conditions/q/pws:KCOBOULD67.json

And there the property wind_gust_mph is "4.0" (with the quotes, so a String). And you cannot parse a string property into an integer. Also the properties for wind_kph and wind_gust_kph are wrong, this should be either string or double:

public string wind_gust_mph { get; set; }
public double wind_kph { get; set; }
public string wind_gust_kph { get; set; }

Hope this helps and merry x-mas.