C# LINQ JOIN + GROUP BY + SUM
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LINQ JOIN + GROUP BY + SUM
提问by JohnBob
I have two LINQ statements that I would like to make into one, but for the life of me I can't get it to work.
我想将两个 LINQ 语句合二为一，但在我的一生中，我无法让它发挥作用。
I can't get the grouping to work in the first statement.
It complains that the TotalBuyand TotalSellproperties aren't there, although doesn't complain about AmountTCand AmountAUD.
我无法在第一个语句中进行分组。它抱怨TotalBuy和TotalSell属性不存在，尽管没有抱怨AmountTC和AmountAUD。
This should be simple. Any thoughts?
这应该很简单。有什么想法吗？
var itineraryItems =
from ii in this.ItineraryItemRecords
join t in this.TransactionRecords on ii.OperatorID equals t.
TransactionActor.OperatorID into g select new {
OperatorID = ii.OperatorID, TotalBuy = g.Sum(i = >ii.TotalBuy)
, TotalSell = g.Sum(i = >ii.TotalSell)
, PaidTC = (0 - (g.Sum(t = >t.AmountTC)))
, PaidAUD = (0 - (g.Sum(t = >t.AmountAUD)))
};
var itineraryItemz =
from i in itineraryItems group i by i.OperatorID into g select new {
OperatorID = g.Key, TotalBuy = g.Sum(i = >i.TotalBuy)
, TotalSell = g.Sum(i = >i.TotalSell)
, PaidTC = (0 - (g.Sum(i = >i.PaidTC)))
, PaidAUD = (0 - (g.Sum(i = >i.PaidAUD)))
};
As a side note, ItineraryItemRecordsand TransactionRecordsare Collections of classes handled by SubSonic.
作为旁注，ItineraryItemRecords和TransactionRecords是由SubSonic.
This really should be simple, so any help would be appreciated.
这真的应该很简单，所以任何帮助将不胜感激。
Regards, John
问候， 约翰
采纳答案by Amy B
A minor mistake, corrected:
一个小错误，更正：
var itineraryItems = from ii in this.ItineraryItemRecords
join t in this.TransactionRecords on ii.OperatorID equals t.TransactionActor.OperatorID
into g
select new
{
OperatorID = ii.OperatorID
//, TotalBuy = g.Sum(i => ii.TotalBuy)
, TotalBuy = g.Sum(i => i.TotalBuy)
//, TotalSell = g.Sum(i => ii.TotalSell)
, TotalSell = g.Sum(i => i.TotalSell)
, PaidTC = (0 - (g.Sum(t => t.AmountTC)))
, PaidAUD = (0 - (g.Sum(t => t.AmountAUD)))
};
I recommend against re-using identifiers - will help avoid these mistakes in the future.
我建议不要重复使用标识符——这将有助于在未来避免这些错误。
