using System;

using System.Collections.Generic;

using System.Linq;

using AutoMapper;

using System.Runtime.Serialization;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        Console.WriteLine($"Configure Mapper");

        var config = new MapperConfiguration(cfg => 

                                             {

                                                 cfg.CreateMap<State, string>().ConvertUsing(src => src.ToString());

                                                 //cfg.AllowNullDestinationValues = true;

                                                //cfg.CreateMap<State, string>().ForMember(dest => dest, opts => {

                                                    //opts.AllowNull();

                                                    //opts.MapFrom(src => src.ToString());

                                                //});

                                                                                      //.MapFrom(src => src));

                                                                                      }

                                            );

        Console.WriteLine($"Create Mapper");

        var mapper = config.CreateMapper();

        Console.WriteLine($"Null As String: {null}");

        var mappedNone = mapper.Map<State?,string>(State.None);

        Console.WriteLine($"Mappd None as String: {mappedNone}");

        List<ClassTest> classTest = new List<ClassTest>();

        classTest.Add(new ClassTest(){State = null, Name = "Null 1"});

        classTest.Add(new ClassTest(){State = "Fail", Name = "Fail 2"});

        classTest.Add(new ClassTest(){State = "Pass", Name = "Pass 1"});

        classTest.Add(new ClassTest(){State = "Pass", Name = "Pass 2"});

        classTest.Add(new ClassTest(){State = "Fail", Name = "Fail 1"});

        var filter = new List<State>(){State.None, State.Pass};

        //var filter = new List<State?>(){null, State.Pass};

        List<string> mappedStrings = mapper.Map<List<string>>(filter);

        foreach(var state in mappedStrings.ToList())

        {

            Console.WriteLine($"Automapped Filters: {state}");

        }

        var statesAsStrings = filter.Select(state => state.ToString()).ToList();

        statesAsStrings.Add(null);

        foreach(var state in statesAsStrings.ToList())

        {

            Console.WriteLine($"Filters: {state}");

        }

        var result = classTest.Where(x => statesAsStrings.Contains(x.State));

        foreach(var test in result.ToList())

        {

            Console.WriteLine($"Name: {test.Name}, State: {test.State}");

        }       

    }

}

​

public enum State

{

    [EnumMember(Value = null)]

    None,

    [EnumMember(Value = "Pass 2")]

    Pass,

    [EnumMember(Value = "Fail 2")]

    Fail

}

​

public class ClassTest

{

    public string State {get;set;}  

    public string Name {get;set;}

}