Linq分组按日期排序然后是时间

Question

Good Evening,

I've managed to get my Linq query almost correct. There is just one more issue I'm struggling to resolve.

My query is

var o =
  (from c in x
   group c by x.Date.Date into cc
   select new 
   { 
      Group = cc.Key.Date, 
      Items = cc.ToList(),
      ItemCount = cc.Count() 
   }).OrderByDescending(p => p.Group);

Now this query works fine. It groups within a ListView by the date. x.Date is a DateTime field in my SQL Database. Therefore I'm selecting x.Date.Date to Group by the actual Date of the DateTime field, as if it was just x.Date it would Group by the date and time.

My question is, how do I group by time so the newest time is at the top of the group?

Many thanks

Answer 1

Use the linq "ThenBy()" method:

var o = (from c in x group c by x.Date.Date into cc select new 
  { 
    Group = cc.Key.Date, 
    Items = cc.OrderByDescending(y=>y.Date).ToList(), 
    ItemCount = cc.Count() 
  })
  .OrderByDescending(p => p.Group)      

Answer 2

将Items = cc.ToList()更改为Items = cc.OrderBy(c => c.[field_you_want_to_sort_by]).ToList()

Answer 3

var o =
  (from c in x
   group c by c.Date.Date into cc
   select new 
   { 
      Group = cc.Key.Date, 
      Items = cc.OrderByDescending(a=>a.Date.Time).ToList(),
      ItemCount = cc.Count() 
   }).OrderByDescending(p => p.Group);