c# - リゾルバーが「エラーマッピングタイプ」をスローするオートマッパー

Question

Automapper を使用してマップする必要があるプロパティとして、別のクラス内にクラスがあります。source クラスのプロパティを destinationMember プロパティにマップするリゾルバーを作成しました。以下のロジックは機能していません。

次のエラーが表示されます。

エラー マッピング タイプ。

マッピング タイプ: SubscriberDTO -> Subscriber ConsoleAutomapperTestHarness.SubscriberDTO -> ConsoleAutomapperTestHarness.Subscriber

タイプ マップ構成: SubscriberDTO -> Subscriber ConsoleAutomapperTestHarness.SubscriberDTO -> ConsoleAutomapperTestHarness.Subscriber

プロパティ: SubscriberSettings

using AutoMapper; //5.1.1.0
using System;

namespace ConsoleAutomapperTestHarness
{
   public class Program
    {
        public static void Main(string[] args)
        {
            SubscriberDTO subDTO = new SubscriberDTO();
            subDTO.AllowAddPFA = true;
            subDTO.AllowAutoPay = true; ;
            subDTO.SubscriberID = 10000;
            subDTO.FirstName = "Kishor";

            new SubscriberAutoMapper();

            Subscriber sub = Mapper.Map<SubscriberDTO, Subscriber>(subDTO);
            Console.WriteLine(sub.SubscriberSettings.AllowAddPFA.ToString());
            Console.ReadLine();
        }
    }

    public class SubscriberAutoMapper
    {
        public SubscriberAutoMapper()
        {
            Mapper.Initialize(cfg => {
                cfg.CreateMap<SubscriberDTO, Subscriber>()
                .ForMember(dest => dest.SubscriberSettings, opt => opt.ResolveUsing<SubscriberAutoMapperResolver>());                
            });
            Mapper.AssertConfigurationIsValid();
        }
    }
    public class SubscriberAutoMapperResolver : IValueResolver<SubscriberDTO, Subscriber, Settings>
    {
        public Settings Resolve(SubscriberDTO source, Subscriber destination, Settings destMember, ResolutionContext context)
        {
            //line which is working.
        return new Settings() { AllowAddPFA = source.AllowAddPFA };

        //line which is not working
       // var result = context.Mapper.Map<SubscriberDTO, Settings>(source);
       // var result = Mapper.Map<SubscriberDTO, Settings>(source);
        //var result = Mapper.Map<SubscriberDTO, Settings>(source,destMember);
        //var result = context.Mapper.Map<SubscriberDTO, Settings>(source, destMember, context);
        //return result;           

        }
    }
    public class Subscriber
    {
        public int SubscriberID { get; set; }
        public Settings SubscriberSettings { get; set; }
        public string FirstName { get; set; }
    }
    public class Settings
    {
        public bool AllowEnrollment { get; set; }
        public bool AllowAutoPay { get; set; }
        public bool AllowAddPFA { get; set; }

    }

    public class SubscriberDTO
    {
        public int SubscriberID { get; set; }
        public string FirstName { get; set; }

        public bool AllowEnrollment { get; set; }
        public bool AllowAutoPay { get; set; }
        public bool AllowAddPFA { get; set; }
    }


}