using System;

using AutoMapper;

public class Program

{

    public static void Main()

    {

        Mapper.CreateMap<Foo, Bar>()

        .ForMember(dest => dest.MyEnum2, opt => opt.MapFrom(src => src.MyEnum1))    

        ;

        var source = new Foo { MyEnum1 = MyEnum1.yellow };

        var destination = Mapper.Map<Bar>(source);

        Console.WriteLine(destination.MyEnum2);

    }

    public class Foo

    {

        public MyEnum1 MyEnum1 { get; set; }    

    }

    public class Bar

    {

        public MyEnum2 MyEnum2 { get; set; }    

    }

    public enum MyEnum1

    {

        red = 1,

        yellow = 2

    }

    public enum MyEnum2

    {

        red = 1,

        yellow = 2

    }

}