C#: How can I make automapper map a property of type object?

Question

This is the source object:

public class Source {
    public object Obj { get; set; }
}

Here object is actually a SourcePropertyType .

I want to convert Source to this:

public class Destination {
    public object Obj { get; set; }
}

where object is DestinationPropertyType (which is identical to SourcePropertyType )

var destination = map.Map<Source, Destination>(source);
var myObj = destination.Obj as DestinationPropertyType;

In the above code myObj == null even if Obj on the source is set.

I hope this makes sense. How can I change the AutoMapper configuration so that it understands that the destination is a DestinationPropertyType and maps it as it would normally?

Answer 1

By "identical to SourcePropertyType " I am assuming you mean that they have the same properties and types. In that case, you just need to have AutoMapper make a map between the two and configure the map for the containing type to use it:

Mapper.CreateMap<SourcePropertyType, DestinationPropertyType>();
Mapper.CreateMap<Source, Destination>()
      .ForMember(d => d.obj,
                 o => o.MapFrom(s => Mapper.Map<DestinationPropertyType>(s.obj As SourcePropertyType) as Object);

Note that if the property types were the actual types instead of object you wouldn't need the extra configuration.

Answer 2

Unbox the objects to specific types before you run it through Automapper. Automapper will not be able to map an object to an object.