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.Text.Json;

using System.Text.Json.Serialization;

​

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

​

//https://stackoverflow.com/questions/58225273/how-to-ignore-false-values-with-system-text-json

​

    public class Model

    {

        public bool Value { get; set; }

    }

​

    public class Model2

    {

        public bool Value { get; set; }

        public double DoubleValue { get; set; }

    }

​

​

    class TestClass

    {

        public static void Test()

        {

            foreach (var value in new [] { false, true })

            {

                var model = new Model { Value = value };

​

                Console.Write("Serializing {0} with value = {1}:  ", model, value);

​

                var options = new JsonSerializerOptions { DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingDefault };

                var json = JsonSerializer.Serialize(model, options);

                Console.WriteLine(json);

                foreach (var doubleValue in new [] { 0.0, 1.0 })

                {

                    var model2 = new Model2 { Value = value, DoubleValue = doubleValue };

​

                    Console.Write("   Serializing {0} with value = {1}, DoubleValue={2}:  ", model2, value, doubleValue);

                    Console.WriteLine(JsonSerializer.Serialize(model2, options));

                }

            }

        }   

    }

​

    public class Program

    {

        public static void Main()

        {

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

            Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.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.Location.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;

        }

    }

​