A better way to use AutoMapper to flatten nested objects?

Question

I have been flattening domain objects into DTOs as shown in the example below:

public class Root
{
    public string AParentProperty { get; set; }
    public         


        

Answer 1

2 more possible solutions:

Mapper.CreateMap<Nested, Flattened>()
    .ForMember(s=>s.AParentProperty, o=>o.Ignore());
Mapper.CreateMap<Root, Flattened>()
    .ForMember(d => d.ANestedProperty, o => o.MapFrom(s => s.TheNestedClass));

An alternative approach would be the below, but it would not pass the Mapper.AssertConfigurationIsValid().

Mapper.CreateMap<Nested, Flattened>()
//.ForMember map your properties here
Mapper.CreateMap<Root, Flattened>()
//.ForMember... map you properties here
.AfterMap((s, d) => Mapper.Map(s.TheNestedClass, d));