using System;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        var json = JsonConvert.SerializeObject(new TestClass {YourValue = new[]{5,4}});

        Console.WriteLine(json);

        var obj = JsonConvert.DeserializeObject<TestClass>(json);

        obj.YourValue.ToArray().Dump();

    }

}

​

class TestClass

{

    [JsonConverter(typeof(MemoryConverter<int>))]

    public Memory<int> YourValue { get; set; } = new[] {1,2,3,4};

}

​

public class MemoryConverter<T> : JsonConverter

{

    public override bool CanConvert(Type objectType) =>

        typeof(Memory<T>).IsAssignableFrom(objectType);

​

    public override bool CanRead => true;

​

    public override bool CanWrite => true;

​

    public override object ReadJson(JsonReader reader, 

                                    Type objectType, 

                                     object existingValue, 

                                     JsonSerializer serializer)

    {

        var mem = new Memory<T>(serializer.Deserialize<T[]>(reader));

        if (existingValue is Memory<T> existingMem && !existingMem.IsEmpty)

        {

            mem.CopyTo(existingMem);

            return existingMem;

        }

        return mem;

    }

​

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)

    {

        if (!(value is Memory<T> mem))

            throw new ArgumentException($"invalid type {value?.GetType().FullName}");

        writer.WriteStartArray();

        var span = mem.Span;

        foreach (var item in span)

        {

            serializer.Serialize(writer, item);

        }

        writer.WriteEndArray();

    }

}