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 Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;    

​

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

​

    //https://stackoverflow.com/questions/55479083/ignoring-implemented-interface-property-for-all-implementations

    //

​

    public interface IFoo 

    {

        [JsonIgnore]

        string SecretProperty  { get; set; }

​

        string Include { get; set; }

    }

​

    public class Foo : IFoo 

    {

        public string SecretProperty  { get; set; }

        public string Include { get; set; }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var root = new Foo

            {

                SecretProperty  = "Ignore Me",

                Include = "Include Me",

            };

            var json = JsonConvert.SerializeObject(root);

​

            Assert.IsTrue(json == "{\"Include\":\"Include Me\"}");// Passes

            Console.WriteLine(json);

            var resolver = new DefaultContractResolver();

​

            var contract = resolver.ResolveContract(typeof(Foo));

            Console.WriteLine("Contract for {0}: {1}", typeof(Foo), contract);

            Console.WriteLine(string.Join("\n", ((JsonObjectContract)contract).Properties.Select(p => string.Format("  {0}: Ignored={1}", p, p.Ignored))));

        }   

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: " + Environment.Version);

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

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

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

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​