在实体框架中的组内排序

Question

我正在使用Entity Framework 6并希望将一些数据分组GROUP BY.我必须对组中的组和数据进行排序.为了让事情变得尽可能简单,我写了一个简约的例子.

我们假设我们有一些文章Created-Field (only Date).我想分组一天写的所有文章.我希望将文章本身分组Created-Field.

这是我的方法:

var articleGroups = DBContext.Articles
    .OrderByDescending(x => x.Created)
    .GroupBy(x => x.Created)
    .OrderByDescending(x => x.Key)
;

这些组被完美地排序,但组本身的排序完全被忽略.我究竟做错了什么？

Answer 1

如果我理解正确的话：

List<Articles> list = new List<Articles>() 
{
   new Articles(){DateCreated=new DateTime(2015, 1, 18), Smth="aa1"},
   new Articles(){DateCreated=new DateTime(2015, 1, 18), Smth="aa2"},
   new Articles(){DateCreated=new DateTime(2014, 1, 18), Smth="aa3"},
   new Articles(){DateCreated=new DateTime(2014, 1, 18), Smth="aa4"},
   new Articles(){DateCreated=new DateTime(2016, 1, 18), Smth="aa5"},
   new Articles(){DateCreated=new DateTime(2016, 1, 18), Smth="aa6"},
   new Articles(){DateCreated=new DateTime(2012, 1, 18), Smth="aa7"},
   new Articles(){DateCreated=new DateTime(2012, 1, 18), Smth="aa8"},
   new Articles(){DateCreated=new DateTime(2018, 1, 18), Smth="aa9"},
   new Articles(){DateCreated=new DateTime(2018, 1, 18), Smth="aa10"},
};
var yourQuery = (from p in list group p.DateCreated by p.DateCreated into g select new { ByDate = g.Key, GroupedColl=g.ToList() }).OrderBy(x=>x.ByDate);

文章类别：

class Articles 
{
    public DateTime DateCreated { get; set; }
    public string Smth { get; set; }
}

哪里ByDate和GroupedColl是您的数据字段。