Question

OK, if I have a class like this …

[serializable]
public class MyClass() : ISerializable
{
  public Dictionary<string, object> Values {get; set;}
}

I know what I have to do to serialize it (the answer, for those trying to find a quick answer, is this)…

protected MyClass(SerializationInfo info, StreamingContext context)
{
  Values = (Dictionary<string, object>)info.GetValue("values", typeof(Dictionary<string, object>));
}

public void GetObjectData(SerializationInfo info, StreamingContext context)
{
  info.AddValue("values", Values);
}

My question is what do I do if, instead, I wanted to defined a class that inherited from Dictionary?

I get this far…

[serializable]
public class MyClass() : Dictionary<string, object>, ISerializable
{
  public void GetObjectData(SerializationInfo info, StreamingContext context)
  {
    info.AddValue("me", this);
  }
}

but then I get lost. I can’t write this …

protected MyClass(SerializationInfo info, StreamingContext context)
{
  this = (MyClass)info.GetValue("me", typeof(MyClass));
}

‘cos ‘this’ is r/o. So, how would I proceed? Am I even right about the implementation of GetObjectData()?

I don’t believe it will make a difference, but just in case it does, I’m writing this under .Net 4.0

Answer 1

Dictionary<T, V> already implements ISerializable (see this). So just call the methods in your base class:

public class MyClass() : Dictionary<string, object>
{
      protected MyClass(SerializationInfo info, StreamingContext context) 
          : base(info, context) // Call the constructor in Dictionary
      {
         // instantiate other properties you had added to MyClass.
      }

      public void GetObjectData(SerializationInfo info, StreamingContext context)
      {
        base.GetObjectData(info, context); 
        // Now add other fields that MyClass implements.
        info.AddValue("whatever", this.AnotherProperty); 
      }
}