How to read Json responce in to DataGridView using RestSharp in C# windows Application

Question

{
  "success": 1,
  "items": [
    {
      "ItemID": "13",
      "ItemName": "Diamond (50 Kg PP)",
      "ItemDesc": "",
      "MRP": "0",
      "Rate": "0",
      "Unit": "",
      "Weight": "50",
      "ItemGroup": ""
    },
    {
      "ItemID": "8",
      "ItemName": "Extra Milk (59 Kg Jute)",
      "ItemDesc": "",
      "MRP": "0",
      "Rate": "0",
      "Unit": "",
      "Weight": "59",
      "ItemGroup": ""
    },
    {
      "ItemID": "19",
      "ItemName": "Extra Milk (59 Kg PP)",
      "ItemDesc": "",
      "MRP": "0",
      "Rate": "0",
      "Unit": "",
      "Weight": "59",
      "ItemGroup": ""
    },
    {
      "ItemID": "23",
      "ItemName": "Test222",
      "ItemDesc": "",
      "MRP": "0",
      "Rate": "0",
      "Unit": "",
      "Weight": "50",
      "ItemGroup": ""
    }
  ]
}

my code

public  async void myweb()
{
    string vJ = "";
    string url = "https://crmscf.vidyasystems.com/api/gen/items.php";
    var client = new RestClient(url);
    var request = new RestRequest();
           
    var responce = client.Get(request);
    // Console.WriteLine(responce.Content.ToString());
    // txtJson.Text = responce.Content.ToString();             

    vJ =  responce.Content.ToString();
    DataTable dataTable = (DataTable)JsonConvert.DeserializeObject(@vJ, (typeof(DataTable)));
    dgvXml.DataSource = dataTable;
}

I am getting error :

Newtonsoft.Json.JsonSerializationException: 'Unexpected JSON token when reading DataTable. Expected StartArray, got StartObject. Path '', line 1, position 1.'

Your JSON does not represent datatable. So you can not deserialize it to datatable. You should create a class structure for your JSON. You can use https://json2csharp.com/. Also you should consider loading data in to the gridview from a List instead of DataTable. This will ease lot of things for you. — Chetan, Aug 15 '22 at 05:50
I have tried to de serialize it class Item, but it is giving Error of invalid charter, if i replace "" with '' it is running well. But as i am reading response from API I have to process as I am getting. — Ketan Patil, Aug 15 '22 at 07:48
Can you share the code which you tried to deserialize from JSON to class? what do you mean by replaceing `""` to `''`. You mean replacing in JSON? There are not `''` in the JSON you shared. What am I missing here? — Chetan, Aug 15 '22 at 08:21
public class stkItem { public string ItemID { get; set; } public string ItemName { get; set; } public string ItemDesc { get; set; } public string MRP { get; set; } public string Rate { get; set; } public string Unit { get; set; } public string Weight { get; set; } public string ItemGroup { get; set; } } — Ketan Patil, Aug 15 '22 at 09:57
stkItem stkIt = Newtonsoft.Json.JsonConvert.DeserializeObject(vJ); but stkIt getting value {"ItemID":null,"ItemName":null,"ItemDesc":null,"MRP":null,"Rate":null,"Unit":null,"Weight":null,"ItemGroup":null} — Ketan Patil, Aug 15 '22 at 09:58

Karen Payne · Accepted Answer · 2022-08-15T11:12:23.613

The following uses a different method to read json. The models and helper class belong in their own files.

using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Net;
using System.Windows.Forms;
using Newtonsoft.Json;

namespace DemoApp
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void ReadJsonButton_Click(object sender, EventArgs e)
        {
            try
            {
                using (var wc = new WebClient())
                {
                    var json = wc.DownloadString("https://crmscf.vidyasystems.com/api/gen/items.php");
                    Container container = JsonConvert.DeserializeObject<Container>(json);
                    if (container != null && container.success == 1)
                    {
                        var dt = container.items.ToList().ToDataTable();
                    }
                    else
                    {
                        // deal with it
                    }
                }
            }
            catch (Exception ex)
            {
                // deal with error
            }

        }
    }


    public class Container
    {
        public int success { get; set; }
        public Item[] items { get; set; }
    }

    public class Item
    {
        public string ItemID { get; set; }
        public string ItemName { get; set; }
        public string ItemDesc { get; set; }
        public string MRP { get; set; }
        public string Rate { get; set; }
        public string Unit { get; set; }
        public string Weight { get; set; }
        public string ItemGroup { get; set; }
    }

    public static class Operations
    {
        public static DataTable ToDataTable<T>(this IList<T> list) 
            => (DataTable)JsonConvert
                .DeserializeObject(JsonConvert.SerializeObject(list), (typeof(DataTable)));
    }

}

Thanks for your reply, I have replicated your code, its working without any error, but not showing any thing DataGridView. I haven't got how u have sent it to DatagridView? — Ketan Patil, Aug 15 '22 at 10:56
See [this](https://github.com/karenpayneoregon/q-a-questions/blob/master/DemoApp/Form1.cs#L28:L29) — Karen Payne, Aug 15 '22 at 11:15

How to read Json responce in to DataGridView using RestSharp in C# windows Application

1 Answers1