using Newtonsoft.Json;

using System;

​

​

namespace ConsoleApp1

{

    class Program

    {

        static void Main(string[] args)

        {

            string json = @"{ ""Start"": ""2020-11-27T16:42:00.000+11:00""}";

            Absense parsed = JsonConvert.DeserializeObject<Absense>(json);

        }

    }

    class Absense

    {

        [Newtonsoft.Json.JsonConverter(typeof(DatetimeJsonConverter))]

        public DateTime Start { get; set; }

    }

​

    class DatetimeJsonConverter : JsonConverter<DateTime?>

    {

        public override DateTime? ReadJson(JsonReader reader, Type objectType, DateTime? existingValue, bool hasExistingValue, JsonSerializer serializer)

        {

            string value = reader.Value?.ToString();

            Console.WriteLine($"{reader.Path}: {value}");

            if (value != null)

            {

                if (DateTimeOffset.TryParse(value, out DateTimeOffset timeOffset))

                {

                    return new DateTime(timeOffset.Year, timeOffset.Month, timeOffset.Day, timeOffset.Hour, timeOffset.Minute, timeOffset.Second);

                }

            }

​

            return existingValue;

        }

​

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

        {

            if (value.HasValue)

            {

                writer.WriteValue(value.Value.ToString("s", System.Globalization.CultureInfo.InvariantCulture));

            }

            else

            {

                writer.WriteNull();

            }

        }

    }

}

​