linq小问题

[a284280221]

	from stg in YTStorageInfo
 	join ptb in YTPlaceToBarInfo
 	on stg.SidVch equals ptb.StorageSidVch
 	join lp in YTLockPlaceInfo
 	on ptb.StorageSidVch equals lp.FidVch
 	group new {stg,lp}
	 by new
	 {
		 ptb.PlaceBarVch,
		 ptb.GoodsBarVch,
		 ptb.TrayBarVch,
		 ptb.StorageSidVch
	 }
	 into tmp
	 select new
	 {
		 placeBarVch = tmp.Key.PlaceBarVch,
		 goodsBarVch = tmp.Key.GoodsBarVch,
		 trayBarVch = tmp.Key.TrayBarVch,
		 amount = tmp.Sum()//这里报错 实例参数: 无法从“System.Linq.IGrouping<AnonymousType#1,AnonymousType#2>”转换为“System.Linq.IQueryable<int>”
	 }

刚学linq 希望高手指教

[q107770540]

tmp里有4个字段，你要为哪个字段进行sum?

amount = tmp.Sum(z=>z.PlaceBarVch)

[devmiao]

amount = tmp.Select(y => y.你要求和的属性).Sum()

[a284280221]

非常感谢