Map a dozen of hierarchical objejcts with AutoMapper to DTOs

Question

I have a hierarchy of 12 entity framework objects.

I have also for each entity a DTO created.

I want to send the DTOs over the wire.

I have to use the DTO-approach.

How would you map this amount of objects with Automapper?

Do I have to use 12 times the AutoMapper.Map method?

UPDATE

I get this error now:

{"Missing type map configuration or unsupported mapping.\r\n\r\n....
I have an NumberEntity.cs with 3 complex properties which I want to map to

a NumberDTO.cs with 3 complex properties.

Is that not possible? Do I have to setup an extra mapping for complex classes within a class?

Answer 1

No, you have to create a mapping for each DTO in config.

Let's say you have a Person.cs, Address.cs, Car and User in your Entities

public class User
{
public int UserId {get;set;}
public string UserName {get;set;}

public PersonDTO Person {get;set;}
}

public class Person
{
public int PersonID {get;set;}
public string Name {get;set;}

public Address Address {get;set;}
public Car Car {get; set;}

}

So you also have PersonDTO, AddressDTO, and CarDTO

e.g.

    public class UserDTO
    {
    public int UserId {get;set;}
    public string UserName {get;set;}

// HERE IF YOU HAVE:
// public PersonDTO MyPerson {get;set;}
// IT WILL NOT MAP
// Property Names should match

    public PersonDTO Person {get;set;}

    }


public class PersonDTO
{
   public int PersonID {get;set;}
   public string Name {get;set;}

   public AddressDTO Address {get;set;}
   public CarDTO Car {get;set;}

}

Your class where you have all Mappings defined.

public class MapperConfig
{
  public static void CreateMappings()
  {
        Mapper.CreateMap<UserDTO, Entities.User>().ReverseMap();
        Mapper.CreateMap<PersonDTO, Entities.Person>().ReverseMap();

        Mapper.CreateMap<AddressDTO, Entities.Address>().ReverseMap();
        Mapper.CreateMap<CarDTO, Entities.Car>().ReverseMap();
  }
}

then in you code:

UserDTO user = Mapper.Map<UserDTO>(context.Users.First(s => s.UserId == 1));

To Map a List:

List<UserDTO> users = Mapper.Map<IEnumerable<UserDTO>>(context.Users).ToList();

As long as the Name of the Properties are the same they should map.