存在以及計算此的替代方法?LINQ通過並正確計數加入羣組
IList<DtoProfile> profileList = Session().QueryOver<DtoProfile>()
IList<Headword> methodList = Session().QueryOver<Headword>()
var hList = profileList.Select(x => x.HeadwordList).SelectMany(x => x).ToList();
profileList包含一個HeadwordList。現在hList包含像
Headword1詞目:ID = 1,文本=文本1(從配置文件1)
Headword2:ID = 2,文本=文本2(從配置文件1)
Headword1:ID = 1,文本文本1 =(從 資料2)
methodList時包含
Headword1:ID = 1,文本=文本1
Headword2:我d = 2,文本=文本2
Headword2:ID = 3,文字=文本3
我想使一個字典等
鍵:文本1,值:2
鍵:文本2,價值:1
鍵:文本3,值:0
var joined = (from headword in methodList
join profile in hList on headword equals profile
group headword by headword.Text
into groupedProfile
select groupedProfile).ToDictionary(x => x.Key, x => x.Count());
它不工作!我只是
鍵:文本1,值:2
鍵:文本2,值:1
在我的字典。 現在我提高到與左連接:
var joined = (from headword in methodList
join profile in hList on headword equals profile into ps
from profile in ps.DefaultIfEmpty()
group headword by headword.Text
into groupedProfile
select groupedProfile).ToDictionary(x => x.Key, x => x.Count(y => y != null));
但Y => Y = null未正常工作! 我得到:
鍵:文本1,值:2
鍵:文本2,值:1
鍵:文本3,值:1(錯了,應該是0)
這些'QueryOver'方法實際返回列表?如果將它保留爲「IQueryable」,您可以更好地優化它。 –