using System;

using SystemJson = System.Text.Json;

using SystemJsonSerialization = System.Text.Json.Serialization;

using NJson = Newtonsoft.Json;

using NJsonConv = Newtonsoft.Json.Converters;

​

public class Program

{

    public record TestRecord(TestEnum Test);

    public enum TestEnum

    {

        Unknown,

        First,

        Second,

        Third

    }

    public static void Main()

    {

        ParseTestRecordSystemText("{\"test\":\"first\"}");

        ParseTestRecordSystemText("{\"test\":\"Second\"}");

        ParseTestRecordSystemText("{\"test\":3}");

        ParseTestRecordNewtonsoft("{\"test\":\"first\"}");

        ParseTestRecordNewtonsoft("{\"test\":\"Second\"}");

        ParseTestRecordNewtonsoft("{\"test\":3}");

    }

    private static void ParseTestRecordSystemText(string jsonString)

    {

        var serializeOptions = new SystemJson.JsonSerializerOptions

        {

            PropertyNamingPolicy = SystemJson.JsonNamingPolicy.CamelCase,

            WriteIndented = true,

                        Converters =

            {

                new SystemJsonSerialization.JsonStringEnumConverter(SystemJson.JsonNamingPolicy.CamelCase)

            }

        };

        var testRecord = SystemJson.JsonSerializer.Deserialize<TestRecord>(jsonString, serializeOptions);

        Console.WriteLine(testRecord.Test);

    }

    private static void ParseTestRecordNewtonsoft(string jsonString)

    {

        var converter = new NJsonConv.StringEnumConverter();

        var testRecord = NJson.JsonConvert.DeserializeObject<TestRecord>(jsonString, converter);

        Console.WriteLine(testRecord.Test);

    }

}