求一个联查再group的sql转成linq

[叫我 Teacher 周]

 SELECT COUNT(A.CheckInUserId) AS CheckInCount, B.UserName 
	FROM ushi_CheckIn AS A INNER JOIN tn_Users AS B
		ON A.CheckInUserID=B.UserID
	GROUP BY B.UserName

换成linq要怎么写啊

[threenewbee]

from A in ushi_CheckIn
join B in tn_Users
on A.CheckInUserID equals B.UserID
groupby B.UserName into g
select new { CheckInCount = g.Count(), UserName = g.Key }

[叫我 Teacher 周]

g.Key是什么

[threenewbee]

groupby B.UserName into g

[叫我 Teacher 周]

引用 1 楼 caozhy 的回复:

from A in ushi_CheckIn join B in tn_Users on A.CheckInUserID equals B.UserID groupby B.UserName into g select new { CheckInCount = g.Count(), UserName = g.Key }

我改成group B by B.UserName 才正确 顺便问一下，如果我还要tn_Users别的字段怎么办

[threenewbee]

xxx = g.First(y => y.B.xxx)

[叫我 Teacher 周]

十分感谢