Ignore base class members when serializing

Question

How do we ignore a particular base class member when serializing an object of derived class?

Background

The base class in my case is UndirectedGraph (from QuickGraph library). Among other things there are two members in this class that I don't want to serialize:

public class UndirectedGraph<TVertex, TEdge>
{
  public IEnumerable<TEdge> Edges { get; }
  public IEnumerable<TVertex> Vertices { get; }
}

So I derived from this class and make my own. I then redefined these two members with new and applied IgnoreDataMember on them. Like this:

public class OurGraph : UndirectedGraph
{
  [IgnoreDataMember]
  public new IEnumerable<XMLDoc> Vertices => base.Vertices;

  [IgnoreDataMember]
  public new IEnumerable<OurEdge> Edges => base.Edges;
}

Now I use DataContractSerializer to write an object of OurGraph to a file:

public static string SerializeDC(this object obj)
{
  XmlSerializerNamespaces Namespaces = new XmlSerializerNamespaces();
  Namespaces.Add(string.Empty, string.Empty);

  System.Text.StringBuilder sb = new System.Text.StringBuilder();

  using (StringWriter writer = new StringWriter(sb))
  {
    using (XmlWriter xmlWriter = XmlWriter.Create(writer, myXmlWriterSettings))
    {
      DSSerializer.WriteObject(xmlWriter, obj);
      xmlWriter.Close();
    }

    writer.Close();
  }

  return sb.ToString();
}

Unfortunately, those two members still find their way into the output. What am I doing wrong?

Edit

While doing further experimentation, it looks like IgnoreDataMember will not work unless you apply DataContract attribute on the containing class. Now applying DataContract attribute on a class requires its base class to also have DataContract (or Serializable ) attribute applied on it, which in my case is a third-party class and I can't change that code.

Am I out of luck?

Answer 1

1. Use Serializable attribute on class.
2. Use NonSerialized attribute on class property for which you don't want to serialize.

Hope this will solve your issue.