列出<T> LINQ Projection to Anonymous或Dynamic类型

Question

我正在尝试List<Topic>通过linq投影将a转换为匿名或动态类型...我正在使用以下代码,但它似乎无法正常工作.它返回动态类型而没有错误,但是,如果我尝试枚举子字段(list<object/topic>)然后它说

结果视图= '<>f__AnonymousType6<id,title,children>'"MyWebCore.dll"和"MvcExtensions.dll"中都存在类型

奇怪.

这是我正在使用的代码:

protected dynamic FlattenTopics()
{
    Func<List<Topic>, object> _Flatten = null; // satisfy recursion re-use
    _Flatten = (topList) =>
    {
        if (topList == null) return null;

        var projection = from tops in topList
                         select new
                         {
                             id = tops.Id,
                             title = tops.Name,
                             children = _Flatten(childs.Children.ToList<Topic>())
                         };
        dynamic transformed = projection;
        return transformed;
    };

    var topics = from tops in Repository.Query<Topic>().ToList()
                 select new
                 {
                     id = tops.Id,
                     title = tops.Name,
                     children = _Flatten(tops.Children.ToList<Topic>())
                 };

    return topics;
}

我正在做的就是压缩一个包含自包含对象的列表 - 基本上它是一个POCO列表,它将被填充到树视图(jstree)中.

Topic类定义为:

public class Topic
{
    public Guid Id {get;set;}
    public string Name {get;set;}
    public List<Topic> Children {get;set;}
}

以下是返回的动态对象的第一个成员的示例:

[0] = { 
    id = {566697be-b336-42bc-9549-9feb0022f348},
    title = "AUTO", 
    children = {System.Linq.Enumerable.SelectManyIterator
          <MyWeb.Models.Topic,
           MyWeb.Models.Topic,
           <>f__AnonymousType6<System.Guid,string,object>
          >} 
 }

Answer 1

这是正确的方法 - 必须加载到 DTO / POCO 并返回：

_Flatten = (topList) =>
        {
            if (topList == null) return null;

            var projection = from tops in topList
                             //from childs in tops.Children
                             select new JsTreeJsonNode
                             {
                                 //id = tops.Id.ToString(),
                                 data = tops.Name,
                                 attr = setAttributes(tops.Id.ToString(), tops.URI),
                                 state = "closed",
                                 children = _Flatten(tops.Children)
                             };


            return projection.ToList();
        };