using System;

using Newtonsoft.Json;

​

public class Program

{

    public static void Main()

    {

        //setup

        var a = new Include{Type = "Baz", Attributes = new Baz{Prop1 = "hello"}};

        //convert

        var b = Convert.ChangeType(a.Attributes, Type.GetType(a.Type));

        //use

        Console.WriteLine(b.Prop1);

    }

}

​

public class Include

{

    [JsonProperty("type")]

    public string Type { get; set; }

​

    [JsonProperty("attributes")]

    public dynamic Attributes { get; set; }

}

​

public class Baz

{

    public string Prop1 { get; set; }

}