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在 LINQ to Entities 查询中没法构造实

发布时间: 2013-01-07 10:02:24 作者: rapoo

在 LINQ to Entities 查询中无法构造实体或复杂类型


//取出文章分类,和分类相应的10篇文章
var query = from t1 in context.Category
select new
{
Category,//分类
Article = (from t2 in context.Article//文章
orderby t2.ModifiedDate descending
where t2.Category.CategoryID == t1.CategoryID
select new Article { ArticleID = t2.ArticleID, Title = t2.Title }).Take(10)
//如果 new Article { ArticleID = t2.ArticleID, Title = t2.Title } 改成
//select t2 就是正常的,但我不只想取出标题和ID,不想全部取出(性能低)

};

var CategoryList = new List<Category>();
if (query != null)
{
foreach (var i in query)//这里出错
{

foreach (var j in i.Article)
{

i.Category.Article.Attach(j);//给分类的Article集合属性 Attach 文章

}



ProductResult.Add(i.Category);

}
}
return CategoryList;



[解决办法]
Article = (from t2 in context.Article//文章
orderby t2.ModifiedDate descending
where t2.Category.CategoryID == t1.CategoryID
select new Article { ArticleID = t2.ArticleID, Title = t2.Title }).ToList().Take(10)
试试 这样

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