“Type not expected”, using DataContractSerializer - but it's just a simple class, no funny stuff?

Question

I\'m refactoring my XML-serialization, and figured I\'d try the DataContractSerializer. Everything runs smoothly, until it needs to serialize this class:

Answer 1

The problem for me was that I was returning the Interface (IIndividual) from my WebAPI controller. When I changed that return type to the Class (Individual) type, this error went away.

Not working:

    [HttpGet]
    [Route("api/v1/Individual/Get/{id}")]
    public IIndividual Get([FromUri]int id)
    {
        return _individualService.Get(id);
    }

Working:

    [HttpGet]
    [Route("api/v1/Individual/Get/{id}")]
    public Individual Get([FromUri]int id)
    {
        IIndividual individual = _individualService.Get(id);
        return individual as Individual;
    }