using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.Data;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

using System.Reflection;

using System.Collections.ObjectModel;

using System.Threading.Tasks;

using System.Buffers;

​

using System.Text.Json;

using System.Text.Json.Serialization;

​

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

​

//https://stackoverflow.com/questions/61665642/how-do-i-deserialize-a-jsondocument-to-a-known-model

​

    public static partial class JsonExtensions

    {

        // Taken from this answer https://stackoverflow.com/a/59047063/3744182

        // To https://stackoverflow.com/questions/58138793/system-text-json-jsonelement-toobject-workaround

        // By https://stackoverflow.com/users/3744182/dbc

        public static T ToObject<T>(this JsonElement element, JsonSerializerOptions options = null)

        {

            var bufferWriter = new ArrayBufferWriter<byte>();

            using (var writer = new Utf8JsonWriter(bufferWriter))

                element.WriteTo(writer);

            return JsonSerializer.Deserialize<T>(bufferWriter.WrittenSpan, options);

        }

​

        public static T ToObject<T>(this JsonDocument document, JsonSerializerOptions options = null)

        {

            if (document == null)

                throw new ArgumentNullException(nameof(document));

            return document.RootElement.ToObject<T>(options);

        }       

    }

​

    public class UILayout

    { 

        public long Version { get; set; }

        public Section[] Sections { get; set; }

    }

​

    public class Section

    {

        public string Label { get; set; }

        public Field[] Fields { get; set; }

    }

​

    public class Field

    {

        public long Order { get; set; }

        public string InternalName { get; set; }

    }

​

    public class Program

    {

        public static async Task Test()

        {

            using var doc = JsonDocument.Parse(GetJson());

            // Ignore case as per this answer https://stackoverflow.com/a/58879380

            // To https://stackoverflow.com/questions/58879190/system-text-json-doesnt-deserialize-what-newtonsoft-does

            // By https://stackoverflow.com/users/12270289/klaycon

            var options = new System.Text.Json.JsonSerializerOptions {PropertyNameCaseInsensitive = true};

            var serializedLayout = doc.RootElement.ToObject<UILayout>(options);

            serializedLayout.Dump();

            Assert.AreEqual(1, serializedLayout.Version);

            Assert.AreEqual(1, serializedLayout.Sections.Length);

            Assert.AreEqual(3, serializedLayout.Sections[0].Fields.Length);

        }

        static string GetJson() 

        {

            return @"{

          ""version"": 1,

          ""sections"": [

            {

              ""label"": ""General Information"",

              ""fields"": [

                {

                  ""order"": 1,

                  ""internalName"": ""a""

                },

                {

                  ""order"": 2,

                  ""internalName"": ""b""

                },

                {

                  ""order"": 3,

                  ""internalName"": ""c""

                }

              ]

            }

          ]

        }";

        }

        public static async Task Main(string[] args)

        {

            Console.WriteLine("Environment version: {0} ({1})", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , GetNetCoreVersion());

            Console.WriteLine("{0} version: {1}", typeof(JsonSerializer).Assembly.GetName().Name,  typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                await Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

        public static string GetNetCoreVersion()

        {

            //https://techblog.dorogin.com/how-to-detect-net-core-version-in-runtime-ecd65ad695be

            //

            var assembly = typeof(System.Runtime.GCSettings).GetTypeInfo().Assembly;

            var assemblyPath = assembly.CodeBase.Split(new[] { '/', '\\' }, StringSplitOptions.RemoveEmptyEntries);

            int netCoreAppIndex = Array.IndexOf(assemblyPath, "Microsoft.NETCore.App");

            if (netCoreAppIndex > 0 && netCoreAppIndex < assemblyPath.Length - 2)

                return assemblyPath[netCoreAppIndex + 1];

            return null;

        }

    }

​