JSON.Net serialize all properties of derived class

Question

I have several classes that are derived from a base class. Base class properties have [DataMember] attribute but derived class properties don't have it. When I use JsonConvert.SerializeObject() on child class object, I see only properties in base class getting serialized unless I add [DataMember] to the property of derived class. How do I make SerializeObject() to serialize all properties of derived class including that of properties defined in base class by ignoring [DataMember] attribute? I want to avoid adding [DataMember] to all properties of derived class.

Answer 1

Without any actual code posted the source of your problem is hard to point out. Maybe you could just drop any de/serialization attributes, like [DataMember()] or [JsonProperty()], and give it another try, since having

public abstract class Base
{
    public abstract string BaseProp { get; }
}

public class MyBase : Base
{
    public override string BaseProp { get { return "propA"; } }
    public string MyBaseProp { get; set; }
}

public class My : MyBase
{
    public string MyProp { get; set; }
}

And then serializing given class instances

var myBase = new MyBase { MyBaseProp = "prop1" };
Console.WriteLine(JsonConvert.SerializeObject(myBase));

var my = new My { MyBaseProp = "prop1", MyProp = "prop2" };
Console.WriteLine(JsonConvert.SerializeObject(my));

Gives you the following output

{"BaseProp":"propA","MyBaseProp":"prop1"}
{"MyProp":"prop2","BaseProp":"propA","MyBaseProp":"prop1"}