https://mahmutgundogdu.wordpress.com/?p=561 makale için gist

SorununCozumu.cs

using System;
using System.Collections.Generic;
using System.Linq;
using AutoMapper;
using AutoMapper.EquivalencyExpression;

public class Program
{
    public static void Main()
    {
        Mapper.Initialize(cfg =>
        {
			     //Nuget ile AutoMapper.Collection  yüklenmeli
            cfg.AddCollectionMappers();
            cfg.CreateMap<MainModel, MainEntity>().ReverseMap();
            cfg.CreateMap<ChildModel, ChildEntity>().EqualityComparison((o, o2) => o.Id == o2.Id);
            cfg.CreateMap<ChildEntity, ChildModel>().EqualityComparison((o, o2) => o.Id == o2.Id);
        });


        MainEntity entity = new MainEntity()
        {
            Id = 1,
            Name = "Name1",
            ChildClasses = new List<ChildEntity>() { new ChildEntity() { Id = 99, Address = "subName2" , MainClassId = 1} }
        };
        MainModel model = new MainModel()
        {
            Id = 1,
            Name = "model Name1",
            ChildClasses = new List<ChildModel>() { new ChildModel() {Id=99, Address = "model subName2" } }
        };
        Mapper.Map(model, entity);
        Console.WriteLine("Name: {0}",entity.Name);
        Console.WriteLine("Address: {0}", entity.ChildClasses.First().Address);
        Console.WriteLine("Id {0}",entity.ChildClasses.First().Id);
        Console.WriteLine("MainClassId {0}", entity.ChildClasses.First().MainClassId);

        Console.WriteLine("the MainClassId should be {0} and it is {1} .its Works!", 1, entity.ChildClasses.First().MainClassId);
        


    }
}

public class MainEntity
{
    public int Id { get; set; }
    public string Name { get; set; }
    public virtual ICollection<ChildEntity> ChildClasses { get; set; }
}
public class ChildEntity
{
    public int Id { get; set; }
    public string Address { get; set; }
    public int MainClassId { get; set; }
}

public class MainModel
{
    public int Id { get; set; }
    public string Name { get; set; }
    public List<ChildModel> ChildClasses { get; set; }
}

public class ChildModel
{
	public int Id { get; set; }
    public string Address { get; set; }
}

SorununTemsil.cs

using System;
using System.Collections.Generic;
using System.Linq;
using AutoMapper;
using AutoMapper.EquivalencyExpression;

public class Program
{
    public static void Main()
    {
        Mapper.Initialize(cfg =>
        {
			
            
            cfg.CreateMap<MainModel, MainEntity>().ReverseMap();
            cfg.CreateMap<ChildModel, ChildEntity>().ReverseMap();
        });


        MainEntity entity = new MainEntity()
        {
            Id = 1,
            Name = "Name1",
            ChildClasses = new List<ChildEntity>() { new ChildEntity() { Id = 99, Address = "subName2" , MainClassId = 1} }
        };
        MainModel model = new MainModel()
        {
            Id = 1,
            Name = "model Name1",
            ChildClasses = new List<ChildModel>() { new ChildModel() {Id=99, Address = "model subName2" } }
        };
        Mapper.Map(model, entity);
        Console.WriteLine("Name: {0}",entity.Name);
        Console.WriteLine("Address: {0}", entity.ChildClasses.First().Address);
        Console.WriteLine("Id {0}",entity.ChildClasses.First().Id);
        Console.WriteLine("MainClassId {0}", entity.ChildClasses.First().MainClassId);

        Console.WriteLine("the MainClassId should be {0} but it is {1}!", 1, entity.ChildClasses.First().MainClassId);
        


    }
}

public class MainEntity
{
    public int Id { get; set; }
    public string Name { get; set; }
    public virtual ICollection<ChildEntity> ChildClasses { get; set; }
}
public class ChildEntity
{
    public int Id { get; set; }
    public string Address { get; set; }
    public int MainClassId { get; set; }
}

public class MainModel
{
    public int Id { get; set; }
    public string Name { get; set; }
    public List<ChildModel> ChildClasses { get; set; }
}

public class ChildModel
{
	public int Id { get; set; }
    public string Address { get; set; }
}