Ignore member of base class in YamlDotNet

Question

I have a class which I want to serialize with YamlDotNet:

public class AwesomeClass : PropertyChangedBase
{
    private bool _element1;
    private bool _enabled;
    
    public bool Element1
    {
        get { return _element1; }
        set
        {
            _element1 = value;
            NotifyOfPropertyChange(() => Element1);
        }
    }
    
    public bool Enabled
    {
        get { return _enabled; }
        set
        {
            _enabled = value;
            NotifyOfPropertyChange(() => Enabled);
        }
    }
}

My problem is, in the base class is an element named: IsNotifying Is there a way to exclude this element from serialization, without the change of the base class?

Answer 1

You could override the property in the derived class and apply the YamlIgnore attribute there. While the sample below works, I suspect for more complicated class hierarchies you would really need to ensure no behavior changes.

public class AwesomeClass : PropertyChangedBase
{
  [YamlIgnore]
  public new bool IsNotifying
  {
    get { return base.IsNotifying; }
    set { base.IsNotifying = value; }
  }

  [YamlIgnore]
  public override bool Blah
  {
    get { return base.Blah; }
    set { base.Blah = value; }
  }
}

public class PropertyChangedBase
{
  public bool IsNotifying
  {
    get;
    set;
  }

  public virtual bool Blah
  {
    get; 
    set;
  }
}

Answer 2

I had a similar problem (needed to filter properties of a particular type from classes I couldn't change, so using the attribute was not an option) and is what I came up with:

1. Create a custom type inspector:

    public class MyTypeInspector : TypeInspectorSkeleton
    {
        private readonly ITypeInspector _innerTypeDescriptor;
   
        public MyTypeInspector(ITypeInspector innerTypeDescriptor)
        {
            _innerTypeDescriptor = innerTypeDescriptor;
        }
   
        public override IEnumerable<IPropertyDescriptor> GetProperties(Type type, object container)
        {
            var props = _innerTypeDescriptor.GetProperties(type, container);
            props = props.Where(p => !(p.Type == typeof(Dictionary<string, object>) && p.Name == "extensions"));
            props = props.Where(p => p.Name != "operation-id");
            return props;
        }
    }
   

2. Create the serializer as follows:

    var builder = new SerializerBuilder();
    builder.WithTypeInspector(inspector => new MyTypeInspector(inspector));
    var serializer = builder.Build();