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I am trying to get data from this Json Rest API and display in View using ASP.NET MVC. I followed this tutorial.

I am getting an error saying 'Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.Collections.Generic.List`1[diversity.Models.Species]' because the type requires a JSON array (e.g. [1,2,3]) to deserialize correctly. To fix this error either change the JSON to a JSON array (e.g. [1,2,3]) or change the deserialized type so that it is a normal .NET type (e.g. not a primitive type like integer, not a collection type like an array or List) that can be deserialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object. Path 'userId', line 2, position 12.'

I am aware of other related questions such as this. However, this suggests to replace <List<Species>> with <Species>. If I did this, it causes error regarding @model IEnumerable<diversity.Models.Species> in the view.

I think the response from the api is a not a list but a single object. Then how can I properly implement this? And If I had to get a list in the future, how should I change the code?

Here is my code.

SpeciesController.cs

using diversity.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using LinqToWiki.Download;
using LinqToWiki.Generated;
using LinqToWiki;
using System.Text;
using RestSharp;
using Newtonsoft.Json.Linq;
using System.Net.Http;
using Newtonsoft.Json;

namespace diversity.Controllers
{
   public class SpeciesController : Controller
  {
    public async System.Threading.Tasks.Task<ActionResult> SpeciesDetails(){

        HttpClient client = new HttpClient();
        List<Species> datalist = new List<Species>();

        try
        {
            HttpResponseMessage response = await client.GetAsync("https://jsonplaceholder.typicode.com/posts/1");
            response.EnsureSuccessStatusCode();
            string responseBody = await response.Content.ReadAsStringAsync();

            datalist = JsonConvert.DeserializeObject<List<Species>>(responseBody);
        }
        catch (HttpRequestException e)
        {
            System.Diagnostics.Debug.WriteLine("\nException Caught!");
            System.Diagnostics.Debug.WriteLine("Message :{0} ", e.Message);
        }
        client.Dispose();
        return View(datalist);
    }
  }
}

Species.cs (Model)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace diversity.Models
{
  public class Species
  {
    public int UserId { get; set; }
    public int Id { get; set; }
    public string Title { get; set; }
    public string Body { get; set; }
  }
}

SpeciesDetails.cshtml

  @model IEnumerable<diversity.Models.Species>

  @{
    ViewBag.Title = "SpeciesDetails";
    Layout = "~/Views/Shared/_Layout.cshtml";
   }

 <h2>SpeciesDetails</h2>

 <p>
    @Html.ActionLink("Create New", "Create")
 </p>

 <table class="table">
 <tr>
    <th>
        @Html.DisplayNameFor(model => model.UserId)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Title)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Body)
    </th>
    <th></th>
</tr>

 @foreach (var item in Model) {
 <tr>
    <td>
        @Html.DisplayFor(modelItem => item.UserId)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Title)
    </td>
    <td>
        @Html.DisplayFor(modelItem => item.Body)
    </td>
    <td>
        @Html.ActionLink("Edit", "Edit", new { id=item.Id }) |
        @Html.ActionLink("Details", "Details", new { id=item.Id }) |
        @Html.ActionLink("Delete", "Delete", new { id=item.Id })
    </td>
  </tr>
 }

</table>
Kabilesh
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0 Answers0