C# Refit Deserialize False to Null when expecting Class

Question

Here are 2 json response examples received when logging in...

For the successful response, payload is a class with id and name

{
    "merchant": "test123",
    "payload": {
        "id": "1234",
        "name": "Test"
    },
    "code": "100",
    "message": "Request successfully executed"
}

...but if the response is unsuccessful I receive the following...

{
    "merchant": "test123",
    "payload": false,
    "code": "105",
    "message": "Invalid username or password!"
}

I have no control over receiving "payload": false. Ideally this would be "payload": null.

How can I change the "payload": false to "payload": null when deserializing the response? Currently getting an exception error at runtime. Using C# and refit.

using System.Text.Json;

namespace Response;

public class ResponseRoot
{
    public string Merchant { get; set; }
    //the value received in the json response needs to become null if the value is false?
    public ResponsePayload? Payload { get; set; }
    public string Code { get; set; }
    public string Message { get; set; }

    public class ResponsePayload
    {
        public string Id { get; set; }
        public string Name { get; set; }
    }
}

Answer 1

you can parse at first

    var jObj = JsonObject.Parse(json);
    if (jObj["payload"].ToString() == "false") jObj["payload"] = null;

    ResponseRoot rb = System.Text.Json.JsonSerializer.Deserialize<ResponseRoot>(jObj, new JsonSerializerOptions
    {
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase
    });

if you have some time and desire you can wrap this code in a function or in a custom json converter.