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;

​

//https://stackoverflow.com/questions/52503025/filter-json-properties-by-name-using-jsonpath

​

    class TestClass

    {

        public static void Test()

        {

            var root = JToken.Parse(GetJson());

            Test1(root);

            Test2(root);

        }

        public static void Test1(JToken root)

        {

            var query = root.SelectTokens("..pass*");

            Console.WriteLine(JsonConvert.SerializeObject(query, Formatting.Indented));

        }

        public static void Test2(JToken root)

        {

            var query = root.SelectTokens("..['pass*']");

            Console.WriteLine(JsonConvert.SerializeObject(query, Formatting.Indented));

        }

​

        static string GetJson()

        {

            var json = @"{

  ""firstName"": ""John"",

  ""lastName"" : ""doe"",

  ""age""      : 50,

  ""pass"" : ""1234"",

  ""phoneNumbers"": [

    {

      ""type""  : ""iPhone"",

      ""number"": ""0123-4567-8888"",

      ""password"": ""abcd""

    },

    {

      ""type""  : ""home"",

      ""number"": ""0123-4567-8910"",

      ""password"": ""fghi""

    }

  ]

}";

            return json;

        }

    }

​

    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;

            }

        }

    }

​