Linq sum and null
本文关键字:null and sum Linq | 更新日期: 2023-09-27 18:19:09
我有查询:
var qq = (from c in db.tblArcadeGames
where
c.IsDeleted == false &&
c.ParentGameID == 0 &&
c.Approved == true
let aggPlays = c.Plays + db.tblArcadeGames.Where(v => v.ParentGameID == c.ID).Sum(v => (int?)v.Plays)
orderby aggPlays descending
select new { c, aggPlays })
.Skip(Skip)
.Take(Fetch);
foreach (var g in qq)
{
HttpContext.Current.Response.Write("{" + g.aggPlays + "}'n");
}
当我在上面的循环中打印出aggPlays
时,它们显示为:
{21}
{}
{}
{}
问题似乎是,如果没有记录存在,Sum()
返回null
。我不知道如何解决这个问题,使c.Plays + null
不等于null
,而只是c.Plays
。
您可以通过不返回int?
,而是直接转换为int
来纠正这个问题:
.Sum(v => v.Plays ?? 0)
int response =
(from p in data.tbHoraires
where p.eid == eid && p.annee == annee && p.obligatoire == true
select (int?)p.nbminute ?? 0).Sum();