创建可屏蔽敏感信息的自定义 json 转换器

Question

我正在编写一个自定义 json 转换器，它将序列化一个对象并屏蔽包含一些敏感信息的某些字段。我已经创建了转换器，但是当我使用转换器序列化对象时，我得到一个空字符串。有人能告诉我我做错了什么吗？public class Student{    public string Name { get; set; }    public string Phone { get; set; }}class StudentJsonConverter : JsonConverter{    /// <inheritdoc />    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)    {        if (value is Student student)        {            student.Phone = MaskString(student.Phone);        }        writer.WriteStartObject();        serializer.Serialize(writer, value);        writer.WriteEndObject();    }    /// <inheritdoc />    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)    {        throw new NotImplementedException();    }    /// <inheritdoc />    public override bool CanConvert(Type objectType) => typeof(Student) == objectType;    private static string MaskString(string sensitiveInformation) => string.IsNullOrWhiteSpace(sensitiveInformation) ? null : new string('*', sensitiveInformation.Length);}我在这里使用它：    JsonSerializerSettings settings = new JsonSerializerSettings();    settings.Converters.Add(new StudentJsonConverter());    settings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;    var student = new Student { Name = "name", Phone = "1234" };    var serializedString = JsonConvert.SerializeObject(student, settings);    Console.WriteLine(serializedString);但我总是得到一个空字符串。