Newton Soft Json JsonSerializerSettings for object with Property as byte array

Question

Using Newton.Json for Json Serializing. What JsonSerializerSettings to apply ,when I have to Json serialize an object with property as Byte array ,and then to display byte array in Hex format..

For eg

class A
{
  public int X {get;set;}
  public byte[] Y {get;set;}  
}

When I serialize A to json , I do not get value for Y as i have set ... Output for byte[] should be in hex

Answer 1

var json = JsonConvert.SerializeObject(new MyTestClass());

public class MyTestClass
{
    public string s = "iiiii";

    [JsonConverter(typeof(ByteArrayConvertor))]
    public byte[] buf = new byte[] {1,2,3,4,5};
}

public class ByteArrayConvertor : Newtonsoft.Json.JsonConverter
{

    public override bool CanConvert(Type objectType)
    {
        return objectType==typeof(byte[]);
    }

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

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        byte[] arr = (byte[])value;
        writer.WriteRaw(BitConverter.ToString(arr).Replace("-", ""));
    }
}

Answer 2

Just overwrite converters in JsonSerializerSettings, better than attribute in properties

private class SerializationTest
{
    public byte[] Bytes => new byte[] { 11, 22, 33, 44, 0xAA, 0xBB, 0xCC };
}

private class ByteArrayHexConverter : JsonConverter
{
    public override bool CanConvert(Type objectType) => objectType == typeof(byte[]);

    public override bool CanRead => false;
    public override bool CanWrite => true;

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

    private readonly string _separator;

    public ByteArrayHexConverter(string separator = ",") => _separator = separator;

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        var hexString = string.Join(_separator, ((byte[])value).Select(p => p.ToString("X2")));
        writer.WriteValue(hexString);
    }
}

private static void Main(string[] args)
{
    var setting = new JsonSerializerSettings { Converters = { new ByteArrayHexConverter() } };
    var json = JsonConvert.SerializeObject(new SerializationTest(), setting);
    Console.WriteLine(json); // {"Bytes":"0B,16,21,2C,AA,BB,CC"}
}