NHibernate projection, AutoMapping, IPagedList, how to? - nhibernate

Question

I have these entities and models:
ENTITIES:
public class BlogPost {
public virtual int Id { get; set; }
public virtual IList<Keyword> Keywords { get; set; }
public virtual IList<BlogComment> Comments { get; set; }
}
public class BlogComment {
public virtual int Id { get; set; }
public virtual BlogPost Post { get; set; }
}
public class Keyword {
public virtual int Id { get; set; }
public virtual IList<BlogPost> BlogPosts { get; set; }
}
VIEW-MODELS:
public class BlogPostModel {
public int Id { get; set; }
// instead of IList<BlogComment> I have this:
public int CommentsCount { get; set; }
public IList<KeywordModel> Keywords { get; set; }
}
public class KeywordModel {
public int Id { get; set; }
public IList<BlogPostModel> Posts { get; set; }
}
public class BlogCommentModel {
public int Id { get; set; }
public BlogPostModel Post { get; set; }
}
Now I want to load a paged-list of blog-posts with their keywords and comments count and map them by AutoMapper library to a IPagedList<BlogPostModel>. Can you help me please? I'm using the Mvc IPagedList available at nuget:
public interface IPagedList<out T> : IPagedList, IEnumerable<T> {
T this[int index] { get; }
int Count { get; }
IPagedList GetMetaData();
}
public interface IPagedList {
int PageCount { get; }
int TotalItemCount { get; }
int PageNumber { get; }
int PageSize { get; }
bool HasPreviousPage { get; }
bool HasNextPage { get; }
bool IsFirstPage { get; }
bool IsLastPage { get; }
int FirstItemOnPage { get; }
int LastItemOnPage { get; }
}
I test many ways and googled the issue, but I can't find any solution. Thanks for any suggestion.

Answer 1

I had the same problem, and found the way how to fix it, probably this approach will help you too.
public class GenericModelViewConverter<TModel, TView> : IModelViewConverter<TModel, TView>
where TModel : class
where TView : class
{
/// <summary>
/// Initializes a new instance of the <see cref="GenericModelViewConverter{TModel, TView}"/> class.
/// </summary>
public GenericModelViewConverter()
{
// It is not he best place to create the mapping here
Mapper.CreateMap<TView, TModel>();
Mapper.CreateMap<TView, TModel>().ReverseMap();
}
/// <summary>
/// Converts the view to model.
/// </summary>
/// <param name="view">The view as a source.</param>
/// <param name="model">The model as a destination value.</param>
/// <returns>The destination model.</returns>
public virtual TModel ConvertViewToModel(TView view, TModel model = null)
{
return model == null ? Mapper.Map<TView, TModel>(view) : Mapper.Map(view, model);
}
/// <summary>
/// Converts the model to view.
/// </summary>
/// <param name="model">The model as a source.</param>
/// <param name="view">The view as a destination.</param>
/// <returns>The destination view.</returns>
public virtual TView ConvertModelToView(TModel model, TView view = null)
{
return view == null ? Mapper.Map<TModel, TView>(model) : Mapper.Map(model, view);
}
/// <summary>
/// Converts the view to model.
/// </summary>
/// <param name="viewCollection">The collection of views.</param>
/// <returns>The collection of models.</returns>
public virtual IEnumerable<TModel> ConvertViewToModel(IEnumerable<TView> viewCollection)
{
return Mapper.Map<IEnumerable<TView>, HashSet<TModel>>(viewCollection);
}
/// <summary>
/// Converts the model to view.
/// </summary>
/// <param name="modelCollection">The collection of models.</param>
/// <returns>The collection of views.</returns>
public virtual IEnumerable<TView> ConvertModelToView(IEnumerable<TModel> modelCollection)
{
return Mapper.Map<IEnumerable<TModel>, HashSet<TView>>(modelCollection);
}
/// <summary>
/// Converts the model to view.
/// </summary>
/// <param name="modelCollection">The model collection.</param>
/// <returns>The collection of models.</returns>
public virtual IPagedCollection<TView> ConvertModelToView(IPagedCollection<TModel> modelCollection)
{
var list = modelCollection.ToList();
var resultList = ConvertModelToView(list);
return new PagedCollection<TView>(resultList, modelCollection.PageIndex, modelCollection.PageSize, modelCollection.TotalItemCount);
}
/// <summary>
/// Converts the view to model.
/// </summary>
/// <param name="viewCollection">The view collection.</param>
/// <returns>The collection of views.</returns>
public virtual IPagedCollection<TModel> ConvertViewToModel(IPagedCollection<TView> viewCollection)
{
var list = viewCollection.ToList();
var resultList = ConvertViewToModel(list);
return new PagedCollection<TModel>(resultList, viewCollection.PageIndex, viewCollection.PageSize, viewCollection.TotalItemCount);
}
}