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var linq = from t1 in mycon.Templet_Down
join t2 in mycon.Templet
on t1.TempletID equals t2.TempletID
join t3 in FriendDS.Tables[0].AsEnumerable()
on t1.UserID equals t3.Field< System.Guid >("FriendID")
select new
{
UserID = userID,
FriendID = t3.Field< System.Guid >("FriendID"),
FriendName = t3.Field < System.String >("FriendName"),
TempletName = t2.TempletName,
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