AutoMapper recursive
- by fra
Hi!
I would like to make a deep copy of a complex object tree using AutoMapper.
The problem is that for each member I would like to construct a new object and then map it, and not simply copying the existing one.
Here it is an example:
public abstract class Test
{
public Test()
{
this.Id = Guid.NewGuid();
}
public Guid Id { get; private set; }
}
public class OuterTest : Test
{
public InnerTest Inner { get; set; }
}
public class InnerTest : Test
{
public int Value { get; set; }
}
and how to test it:
OuterTest outerDest = Mapper.Map<OuterTest, OuterTest>(outerSource);
System.Diagnostics.Debug.WriteLine("InnerSource id: " + innerSource.Id);
System.Diagnostics.Debug.WriteLine("InnerSource value: " + innerSource.Value);
System.Diagnostics.Debug.WriteLine("OuterSource id: " + outerSource.Id);
System.Diagnostics.Debug.WriteLine("OuterDest id: " + outerDest.Id);
System.Diagnostics.Debug.WriteLine("OuterDest.Inner id: " + outerDest.Inner.Id);
System.Diagnostics.Debug.WriteLine("OuterDest.Inner value: " + outerDest.Inner.Value);
This is the result from the output window:
InnerSource id: a60fda37-206a-40a8-a7f8-db480149c906
InnerSource value: 2119686684
OuterSource id: 7486899e-2da8-4873-9160-d6096b555c73
OuterDest id: 7486899e-2da8-4873-9160-d6096b555c73
OuterDest.Inner id: a60fda37-206a-40a8-a7f8-db480149c906
OuterDest.Inner value: 2119686684
The problem is thet the object innerSource is always the same instance as outerDest.Inner (I verified through MakeObjectId of VS debugger) but I would like them to be two different instances.
How could I create a recursive map with this behavior? I tried creating a custom IValueResolver like the following, without success.
public class AutoMapperNewObjectResolver : IValueResolver
{
public ResolutionResult Resolve(ResolutionResult source)
{
object resolved;
if (source.Value != null)
{
object instance = Activator.CreateInstance(source.MemberType);
resolved = Mapper.Map(source.Value, instance, source.MemberType, source.MemberType);
}
else
{
resolved = null;
}
ResolutionResult result = source.New(resolved, source.Context.DestinationType);
return result;
}
}
and configured like this:
Mapper.CreateMap<OuterTest, OuterTest>()
.ForMember(d => d.Inner, o => o.ResolveUsing<AutoMapperNewObjectResolver>().FromMember(src => src.Inner));
Any help appreciated, thank you
