c# - group by multiple Columns and Select specific columns -

how can groupby multiple columns in linq , want take of columns:

public class notification {     [key]     [databasegeneratedattribute(databasegeneratedoption.identity)]     public long notificationid { set; get; }       public notificationtype notificationtype { set; get; }       public int userid { get; set; }     public userprofile userprofile { get; set; }       public datetime createdate { set; get; }        public bool notice { set; get; }       public long newsid { set; get; }       public int recipientid { get; set; } } 

i have written following code, displays records:

var x=(from n in _notification                 n.recipientid == id                 orderby n.createdate descending, n.userid                 group new { n.userid, n.newsid}                 new { n.userid, n.newsid, n.notice, n.notificationtype, n.createdate, n.notificationid, n.userprofile } g                 select new notificationviewmodel                 {                     newsid = g.key.newsid,                     causerid = g.key.userid,                     causername = g.key.userprofile.name,                     createdate = g.key.createdate,                     notice = g.key.notice,                     notificationid = g.key.notificationid,                     notificationtype = g.key.notificationtype,                 }).tolist(); 

i want grouped according userid , newsid

you 1 listed instead of grouped list because @ end have select statement while should have group @ end. change code this:

var x=(from n in _notification             n.recipientid == id             orderby n.createdate descending, n.userid             group new notificationviewmodel             {                 newsid = g.key.newsid,                 causerid = g.key.userid,                 causername = g.key.userprofile.name,                 createdate = g.key.createdate,                 notice = g.key.notice,                 notificationid = g.key.notificationid,                 notificationtype = g.key.notificationtype,             }             new { n.userid, n.newsid}).tolist();