AutomapperTest

AutoMapperTestEntities.cs

using System;

namespace AutoMapperTest.CLI
{
    class PersonDTO
    {
        public Guid? ID { get; set; }
        public string Name { get; set; }
        public int? Age { get; set; }
        public string Description { get; set; }        
    }

    class Person
    {
        public Guid ID { get; set; }
        public string Name { get; set; }
        public int Age { get; set; }
        public string Description { get; set; }
    }
}

AutoMapperTestProgram.cs

using AutoMapper;
using System;

namespace AutoMapperTest.CLI
{
    class Program
    {
        static void Main(string[] args)
        {
            Mapper.Initialize(config =>
            {
                config.CreateMap<PersonDTO, Person>().ForAllMembers(opts => opts.Condition((src, dest, srcMember) => srcMember != null));

                //specific for int? in source and int in destination
                //config.ForAllPropertyMaps(pm => pm.SourceType == typeof(int?) && pm.DestinationType == typeof(int), (pm, mo) => mo.UseDestinationValue());

                //generic for matching nullable in source and non nullable in destination
                config.ForAllPropertyMaps(pm => Nullable.GetUnderlyingType(pm.SourceType) == pm.DestinationType, (pm, mo) => mo.UseDestinationValue());
            });

            var dto = new PersonDTO { ID = null, Name = "namedto", Age = 140, Description = "descriptiondto" };
            var entity = new Person { ID = Guid.Parse("1658f9e3-e361-4ac5-a9a1-d57e43b3e135"), Name = "name", Age = 40, Description = "description" };

            Mapper.Map(dto, entity);

            Console.WriteLine("ID:" + entity.ID);//1658f9e3-e361-4ac5-a9a1-d57e43b3e135
            Console.WriteLine("Name:" + entity.Name);//namedto
            Console.WriteLine("Description:" + entity.Description);//descriptiondto
            Console.WriteLine("Age:" + entity.Age);//140
        }
    }
}