xamarin.forms - Newtonsoft.Json.JsonSerializationException：转换值时出错

Question

我是 Xamarin.Forms 的新手。我正在尝试反序列化 JSON 字符串以显示到列表视图中。我成功地从服务器获取了 JSON 字符串，但是在尝试反序列化它时，它会抛出这个错误：

Newtonsoft.Json.JsonSerializationException: Error converting value "El Rey Cantina TRC" to type 'App7.Page1+Place[]'. Path 'titulo', line 1, position 30.

这是我的代码：

namespace App7
{
    public partial class Page1 : ContentPage
    {
        static ListView lstPlaces = new ListView();

        public Page1()
        {

            //borrar
            Button newButn = new Button()
            {

                Text = "Connect to Service",
                TextColor = Color.FromHex("#333333"),
                HorizontalOptions = LayoutOptions.Center

            };

            Content = new StackLayout
            {

                Children = {

                    newButn,
                    lstPlaces

                }

            };
            //borrar

            //click
            newButn.Clicked += newButn_Clicked;
            lstPlaces.ItemTemplate = new DataTemplate(typeof(TextCell));
            lstPlaces.ItemTemplate.SetBinding(TextCell.TextProperty, "titulo");
            //click

        }

        async void newButn_Clicked(object sender, EventArgs e)
        {
            //que pedo
            GeoNamesWebService geoService = new GeoNamesWebService();
            Place[] places = await geoService.GetPlacesAsync();
            lstPlaces.ItemsSource = places;
        }

        public class GeoNamesWebService
        {
            public GeoNamesWebService()
            {
            }
            public async Task<Place[]> GetPlacesAsync()
            {
                var client = new System.Net.Http.HttpClient();
                client.BaseAddress = new Uri("http://www.catcherapp.net/");
                StringContent str = new StringContent("postalcode=752020&country=IN&username=nirmalh", Encoding.UTF8, "application/x-www-form-urlencoded");
                var response = await client.PostAsync(new Uri("http://www.catcherapp.net/borrar/borrar.php"), str);
                var placesJson = response.Content.ReadAsStringAsync().Result;
                Placeobject placeobject = new Placeobject();
                if (placesJson != "")
                {
                    placeobject = JsonConvert.DeserializeObject<Placeobject>(placesJson);
                }
                return placeobject.places;
            }
        }


        public class Placeobject
        {
            [JsonProperty("titulo")]
            public Place[] places { get; set; }
        }
        public class Place
        {
            public string placeName { get; set; }
        }

    }
}

json字符串：

{"titulo":"Bistro Garden","idE":"gb54ezpjs9k0es8w5q","pp":"sge39na6rbpp7uudgk.jpg","direccion":"Feliciano Cobian #570, Col. Nueva Los Angeles, Torre\u00f3n","contador":null}

知道我做错了什么吗？

Answer 1

您的 JSON 属性“titulo”是一个字符串，而不是 Place 数组。 json 对象需要是：

{ 
   "titulo":[
         {"placeName":"place1"},
         {"placeName":"place2"}]
}