using System;

using AutoMapper;

public class Program

{

    public static void Main()

    {

        var a = new A()

        {

            AnyName = new() { Parameter = "123" }

        };

​

        var configuration = new MapperConfiguration(cfg =>

        {

            cfg.AddProfile<MainProfile>();

        });

​

        IMapper mapper = configuration.CreateMapper();

​

        var b = mapper.Map<B>(a);

​

        Console.WriteLine(b.AnyNameParameter);

    }

}

​

public class A

{

    public NestedClass AnyName { get; set; }

}

​

public class B

{

    public string AnyNameParameter { get; set; }

}

​

public class NestedClass

{

    public string Parameter { get; init; }

}

​

public class MainProfile : Profile

{

    public MainProfile()

    {

        CreateMap<A, B>();

    }

}