Automapper : mapping issue with inheritance and abstract base class on collections with Entity Framework 4 Proxy Pocos

Question

I am having an issue using AutoMapper (which is an excellent technology) to map a business object to a DTO where I have inheritance off of an abstract base class within a co

Answer 1

Building on Olivier's response, I could not get his to work in my context... it kept going in an infinite loop and threw a StackOverflowException.

In this example, AbstractClass is my base class and AbstractViewModel is my base view model (not marked as abstract mind you).

However, I did get it to work using this hackish looking converter:

    public class ProxyConverter : ITypeConverter
        where TSource : class
        where TDestination : class
    {
        public TDestination Convert(ResolutionContext context)
        {
            // Get dynamic proxy base type
            var baseType = context.SourceValue.GetType().BaseType;

            // Return regular map if base type == Abstract base type
            if (baseType == typeof(TSource))
                baseType = context.SourceValue.GetType();

            // Look up map for base type
            var destType = (from maps in Mapper.GetAllTypeMaps()
                           where maps.SourceType == baseType
                           select maps).FirstOrDefault().DestinationType;

            return Mapper.DynamicMap(context.SourceValue, baseType, destType) as TDestination;
        }
    }

    // Usage

    Mapper.CreateMap()
        .ConvertUsing(new ProxyConverter());

So, a DerivedClassA will map normally, but a DynamicProxy_xxx will also map properly as this code inspects its base type (DerivedClassA).

Please, please, please show me that I don't have to do this crazy lookup crap. I don't know enough AutoMapper to fix Olivier's answer properly.