How to exclude a property from being serialized in System.Text.Json.JsonSerializer.Serialize() using a JsonConverter

Question

I want to be able to exclude a property when serializing using System.Text.Json.JsonSerializer. I don\'t want to use a JsonIgnore attribute everywhere I want to

Answer 1

Option 1 - Cast to Interface

1. Extract interface which describes structure of desired object.

   public interface IBook
   {
       public int Id { get; set; }
       public string Name { get; set; }
   }
   

2. Implement it on the original class class Book : IBook

3. Use the follow overload of string Serialize(object value, Type inputType, JsonSerializerOptions options = null);

   json = JsonSerializer.Serialize(book, typeof(IBook), options);
   

   If you're serializing array of Books (plural), you'll need to pass typeof(IEnumerable) as an argument.

Option 2 - Use AutoMapper

This is useful if you don't have access to the original Book class.

1. Create LiteBook class:

   public class LiteBook
   {
       public int Id { get; set; }
       public string Name { get; set; }
   }
   

2. Create mapping configuration:

   var config = new MapperConfiguration(cfg => {
       cfg.CreateMap();
   });
   

3. Map it and serialize

   json = JsonSerializer.Serialize(new Mapper(config).Map(book), options)