Linq 2 SQL分組問題

Question

var groups = from p in dc.Pool 
      join pm in dc.PoolMembers on p.ID equals pm.PoolID 
      group p by p.Group into grp 
      select new { grp.ID }; 

這不起作用。基本上我想要做分組，然後選擇某些列，但是當我做select new { grp. }時我沒有任何智能感知，所以我顯然做錯了什麼。

任何想法？

Answer 1

我不確定但是，下面的代碼工作嗎？

var groups = from p in dc.Pool 
      join pm in dc.PoolMembers on p.ID equals pm.PoolID 
      group p by p.Group into grp 
      select grp.Select(g=> g.ID); 

編輯

var groups = from p in dc.Pool 
      join pm in dc.PoolMembers on p.ID equals pm.PoolID 
      group p by p.Group into grp 
      select grp.Select(g=> new{ 
        Id = g.Id, 
        GroupName = grp.Key.Name, 
        Contribution = pm.Contribution, 
        GameName = p.GameName, }); 

Answer 2

我認爲這是你在找什麼

 var groups = from p in dc.Pool 
       join pm in dc.PoolMembers on p.ID equals pm.PoolID 
       group p by p.Group into grp 
       select new { grp.Key.ID, GroupName = grp.Key.Group.Name, grp.Key.GameName }; 

Answer 3

var pools = 
    from p in dc.Pool 
    select new 
    { 
    p.ID, 
    GroupName = p.Group.Name, 
    Contribution = p.PoolMembers.Sum(pm => pm.Contribution), 
    p.GameName 
    };