如何在c#中更改JSON响应中的日期格式

using System;
using Newtonsoft.Json;

public class CustomDateTimeConverter : JsonConverter
{
    private const string DateFormat = "yyyy-MM-dd";

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        DateTime dateTime = (DateTime)value;
        writer.WriteValue(dateTime.ToString(DateFormat));
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }

    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(DateTime);
    }
}

using Newtonsoft.Json;

public class MyClass
{
    [JsonConverter(typeof(CustomDateTimeConverter))]
    public DateTime MyDate { get; set; }
}

MyClass myObject = new MyClass { MyDate = DateTime.Now };
string json = JsonConvert.SerializeObject(myObject);