How do you modify the Json serialization of just one field using Json.net?

Question

Say for example I\'m trying to convert an object with 10 fields to Json, however I need to modify the process of serializing 1 of these fields. At the moment, I\'d have to use m

Answer 1

You can try by decorating the property you need to modify manually with JsonConverterAttribute and pass the appropriate JsonConverter type.

For example, using OP's original example:

public class IntegerConverter : JsonConverter
{
  public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
  {
    serializer.Serialize(writer, Convert.ToInt32(value));
  }

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

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

class TestJson
{
  public string Field1 { get; set; }
  public string Field2 { get; set; }
  public string Field3 { get; set; }

  [JsonConverter(typeof(IntegerConverter))]
  public string Field4 { get; set; }        
}

You can then serialize the object as usual using JsonConvert:

var test = new TestJson {Field1 = "1", Field2 = "2", Field3 = "3", Field4 = "4"};

var jsonString = JsonConvert.SerializeObject(test);