Serializing objects to JSON with properties that return interfaces

[Ra Carter]

I want to serialize and deserialize an object to and from JSON. My
code looks something like this:

http://pastebin.com/yB5idwNq

This gives me an error like this:

System.Runtime.Serialization.SerializationException: Type 'MyObject1'
with data contract name 'MyObject1:http://schemas.datacontract.org/
2004/07/namespace' is not expected. Add any types not known statically
to the list of known types - for example, by using the
KnownTypeAttribute attribute or by adding them to the list of known
types passed to DataContractSerializer.

I am only using ISerializable because [Serializable] [DataContract]
would not work of course. The main problem I think I am having is that
I have declared my return type as an interface.

I don't want to change my objects and it is actually important that I
return the interface and not the implementation for various reasons.
What can be done? if Serializable or DataContract attributes won't
work automatically, can I pull this off manually using Serializable?

 

[sloan]

http://social.msdn.microsoft.com/Forums/en-US/wcf/thread/6b70e9f4-52bc-4fa9-a0ff-c0859e041e85
http://blogs.msdn.com/sowmy/archive/2006/06/06/all-about-knowntypes.aspx

Please post your solution after you figure out, so others can learn from it.