Automapper not mapping IEnumerable<T> to IEnumerable<T> in Viewmodel

Question

I have the following classes defined;

Data.Models.Lists.List

Infrastructure.Models.Lists.List

Both contain the following fields;

public int Id { get; set; }

public string Description { get; set; }

I also have this View Model defined;

public class IndexViewModel
{
     public IEnumerable<Infrastructure.Models.Lists.List> Lists { get; set; }
}

Within my Automapper configuration, I am simply doing the following;

cfg.CreateMap< Data.Models.Lists.List, Infrastructure.Models.Lists.List>()

Which I thought would be enough, but I also added this;

cfg.CreateMap<IEnumerable<List>,Models.Lists.IndexViewModel>();

However, when I attempt to map the items in my controller;

var items = ListsService.GetLists(CurrentPrincipal.Id);

var model = Mapper.Map<IndexViewModel>(items);

model.Lists is always null, although items has 22. What else needs to be added in order to get this mapping working?

Answer 1

AutoMapper does automatic mapping of the properties of the two types with the same name.

In order to map the whole source object to a target object property as in your case, you have to specify that explicitly:

cfg.CreateMap<IEnumerable<Data.Models.Lists.List>, Models.Lists.IndexViewModel>()
    .ForMember(dest => dest.Lists, m => m.MapFrom(src => src));

Answer 2

You are mapping your items to the instance of the viewmodel directly, not it's Lists property. Your first mapping config is fine, the second one you don't need.

var model = new IndexViewModel()
{
    Lists = Mapper.Map<IEnumerable<Infrastructure.Models.Lists.List>>(items)
};