using System;

using AutoMapper;

​

public class Item

{

    public MovieMetadata MovieMetadata { get; set; }

​

    public BookMetadata BookMetadata { get; set; }

}

​

public class MovieMetadata

{

    public string Title { get; set; }

}

​

public class BookMetadata

{

    public string Title { get; set; }

}

​

public class ItemDetail

{

    public string Title { get; set; }

}

​

public class ItemProfile : Profile

{

    public ItemProfile()

    {

        CreateMap<Item, ItemDetail>(MemberList.None)

            .AfterMap((src, dest, ctx) => 

            {

                if (src.BookMetadata != null)

                {

                    ctx.Mapper.Map(src.BookMetadata, dest);

                }

                else if (src.MovieMetadata != null)

                {

                    ctx.Mapper.Map(src.MovieMetadata, dest);

                }

            });

​

        CreateMap<BookMetadata, ItemDetail>();

​

        CreateMap<MovieMetadata, ItemDetail>();

    }

}

public class Program

{

    public static void Main()

    {

        //create mapper

        var configuration = new MapperConfiguration(cfg =>

        {

            cfg.AddMaps(typeof(ItemProfile));

        });

        var mapper = configuration.CreateMapper();

        //check if configuration valid

        mapper.ConfigurationProvider.AssertConfigurationIsValid();

        Console.WriteLine("Mapper configuration is valid");

        //try map book metadata

        var bookItem = new Item

        {

            BookMetadata = new BookMetadata()

            {

                Title = "book"

            },

            MovieMetadata = null

        };

        var bookItemDetail = mapper.Map<ItemDetail>(bookItem);

        bool isBookCorrectlyMapped = bookItem.BookMetadata.Title == bookItemDetail.Title;

        Console.WriteLine($"Book mapped correctly: {isBookCorrectlyMapped}");

        //try map movie metadata

        var movieItem = new Item

        {

            BookMetadata = null,

            MovieMetadata = new MovieMetadata()

            {

                Title = "movie"

            }

        };

        var movieItemDetail = mapper.Map<ItemDetail>(movieItem);

        bool isMovieCorrectlyMapped = movieItem.MovieMetadata.Title == movieItemDetail.Title;

        Console.WriteLine($"Movie mapped correctly: {isMovieCorrectlyMapped}");

    }

}