Mapping complex inherited models with Automapper

Question

I am working on my .NET Core 3.0 app and I need to map my model into another model with Automapper (I have ddl-s and need to use those libraries).

My model (source model) has following structure:

public class ProfessorModel {
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
    public string Profession { get; set; }
    public string JobId { get; set; }
}

public class UniversityMembersModel {
    public IEnumerable<ProfessorModel> People { get; set; }
}

Destination model is following:

public interface Identificator {
    int Id { get; }
}

public interface IPerson : Identificator {
    string FirstName { get; }
    string LastName { get; }
}

public abstract class TeachingStaff : IPerson, Identificator {
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Email { get; set; }
}

public class TeachingProfessor : TeachingStaff {
    public string Profession { get; set; }
    public string TeachingSubject { get; set; }
    public string JoblId { get; set; }
}

public class UniversityMembers {
    public IEnumerable<IPerson> People { get; set; }
}

I was not able to get right mapping into destination model. I have tried with following Automapper configurations:

var config = new MapperConfiguration(cfg => {
    cfg.CreateMap<ProfessorModel, IPerson>(); // <-- does not work

    // does not work:
    cfg.CreateMap<ProfessorModel, IPerson>()
        .ConstructUsing(p => new TeachingProfessor());

    // does not work:
    cfg.CreateMap<ProfessorModel, TeachingProfessor>();

    // does not work:
    cfg.CreateMap<ProfessorModel, TeachingProfessor>()
        .ConstructUsing(p => new TeachingProfessor());
});

The response I need to map from source into destination model is following:

{
    "people": [
        {
            "id": 213,
            "firstName": "John",
            "lastName": "Doe",
            "email": "[email protected]",
            "profession": "Full time professor Biology",
            "jobId": "J3487H"
        },
        {
            "id:" 928,
            "firstName": "Mary",
            "lastName": "Doe",
            "email": "[email protected]",
            "profession": "Part time professor Chemistry",
            "jobId": "P3436JJ"
        }
    ]
}

How could I get mapped destination model from the source one? I cannot change structure from my destination model because is defined in existing .dll library. I also didn't find any solutions in the documentation about inherited abstract classes and interfaces.

Thanks everyone!

Could you elaborate on what "does not work" mean? Are you getting exceptions? Syntax errors? — Xerillio

ZPA ZPA · Accepted Answer · 2020-11-30T08:25:30

I have reviewed some StackOverflow answers and finally came with following workable solution.

I have created custom converter:

public class ProfessorIPersonConverter : ITypeConverter<src.Professor, dest.IPerson>
    {
        public IPerson Convert(Professor source, IPerson destination, ResolutionContext context)
        {
            return context.Mapper.Map<src.Professor, dest.TeachingProfessor>(source);
        }
    }

which was then included into existing mapper configuration:

var config = new MapperConfiguration(cfg => {
    cfg.CreateMap<src.Professor, dest.IPerson>()
       .ConvertUsing(new ProfessorIPersonConverter());
    cfg.CreateMap<src.Professor, dest.TeachingProfessor>();
});

It works like a charm :)

Mapping complex inherited models with Automapper

1 Answers