如何解决AutoMapper错误？ （stackoverflow异常！）

Question

我在以下课程中使用AutoMapper + EF（实体=＆gt; POCO）：

public class Category
{
    public int CategoryID { get; set; }

    public string Name { get; set; }

    public Category Parent { get; set; }

    public IList<Category> Children { get; set; }
}

由于此类与其自身（父/子）有关系，因此AutoMapper发疯并抛出了Stackoverflow异常。你有没有遇到过这个问题？

Answer 1

我通过创建自定义值解析器解决了这个问题。这不是美好的事情，但它正在发挥作用。

Mapper.CreateMap<Category, CategoryDTO>()
                .ForMember(c => c.Parent, opt => opt.ResolveUsing<ParentResolver>())
                .ForMember(c => c.Children, opt => opt.ResolveUsing<ChildrenResolver>());

Mapper.CreateMap<CategoryDTO, Category>()
                .ForMember(c => c.Parent, opt => opt.ResolveUsing<ParentDTOResolver>())
                .ForMember(c => c.Children, opt => opt.ResolveUsing<ChildrenDTOResolver>());


public class ParentResolver : ValueResolver<Category, CategoryDTO>
    {
        protected override CategoryDTO ResolveCore(Category category)
        {
            CategoryDTO dto = null;

            if (category.Parent != null)
                dto = Mapper.Map<Category, CategoryDTO>(category.Parent);

            return dto;
        }
    }

    public class ParentDTOResolver : ValueResolver<CategoryDTO, Category>
    {
        protected override Category ResolveCore(CategoryDTO category)
        {
            Category poco = null;

            if (category.Parent != null)
                poco = Mapper.Map<CategoryDTO, Category>(category.Parent);

            return poco;
        }
    }

    public class ChildrenResolver : ValueResolver<Category, EntityCollection<CategoryDTO>>
    {
        protected override EntityCollection<CategoryDTO> ResolveCore(Category category)
        {
            EntityCollection<CategoryDTO> dtos = null;

            if (category.Children != null && category.Children.Count > 0)
                dtos = Mapper.Map<IList<Category>, EntityCollection<CategoryDTO>>(category.Children);

            return dtos;
        }
    }

    public class ChildrenDTOResolver : ValueResolver<CategoryDTO, IList<Category>>
    {
        protected override IList<Category> ResolveCore(CategoryDTO category)
        {
            IList<Category> pocos = null;

            if (category.Children != null && category.Children.Count > 0)
                pocos = Mapper.Map<EntityCollection<CategoryDTO>, IList<Category>>(category.Children);

            return pocos;
        }
    }

Answer 2

这似乎是一个已知问题。 Automapper进入了一个无限循环。

以下是设法解决此问题的人的链接：

http://blogs.ugidotnet.org/lmauri/archive/2009/05/02/automapper-efpocogenerator-entityframework-and-associations.aspx

这里添加的是此页面翻译版本的链接：）

http://translate.google.com/translate?hl=en&sl=it&u=http://blogs.ugidotnet.org/lmauri/archive/2009/05/02/automapper-efpocogenerator-entityframework-and-associations.aspx&ei=UneASvahFoPe-Qa_38RU&sa=X&oi=translate&resnum=2&ct=result&prev=/search%3Fq%3Dstackoverflow%2Bautomapper%26hl%3Den%26sa%3DN%26start%3D20