using System;

using System.Collections.Generic;

using System.Globalization;

using System.Text.Json;

public class Program

{

    public static void Main()

    {

        CultureInfo.CurrentCulture = new CultureInfo("fr-FR");

        DateTime entry = DateTime.Now;

        string jsonString = JsonSerializer.Serialize(entry, new JsonSerializerOptions { WriteIndented = true });

        Console.WriteLine(jsonString);

        KeyValuePair<string, DateTime> deserialized = JsonSerializer.Deserialize<KeyValuePair<string, DateTime>>("{\"date\":\"2022-11-27T10:28:16.6457032+00:00\"}");

        CultureInfo.CurrentCulture = new CultureInfo("fr-FR");

        Console.WriteLine("Date: "+deserialized.Value.ToString("D"));

    }

}