在 vb.net 中使用 linq 分组数据表
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Datatable group by with linq in vb.net
提问by Nick
I'm trying to get aggregate values from data table. But can't figure out how. Saw some examples in c#, but couldn't translate those to vb.net.
我正在尝试从数据表中获取聚合值。但想不通怎么办。在 c# 中看到了一些示例，但无法将它们转换为 vb.net。
I have data table
我有数据表
Month, campaign, sales, leads, gross
1 1 5 10 1000
1 2 0 5 0
2 1 2 0 300
2 2 1 3 200
I need to get a result :
我需要得到一个结果：
Month, sales, leads, gross
1 5 15 1000
2 3 3 500
I don't want to loop and combine values manually. Please help
我不想手动循环和组合值。请帮忙
回答by Tim Schmelter
You want to Group by Month? You can use Sumto sum the groups:
你想Group by Month吗？您可以使用Sum对组求和：
Dim query = From row In dt
Group row By Month = row.Field(Of Int32)("Month") Into MonthGroup = Group
Select New With {
Key Month,
.Sales = MonthGroup.Sum(Function(r) r.Field(Of Int32)("Sales")),
.Leads = MonthGroup.Sum(Function(r) r.Field(Of Int32)("Leads")),
.Gross = MonthGroup.Sum(Function(r) r.Field(Of Int32)("Gross"))
}
For Each x In query
Console.WriteLine("Month:{0} {1} {2} {3}", x.Month, x.Sales, x.Leads, x.Gross)
Next
This is a mixture of Linq query- and method-syntax.
这是 Linq 查询和方法语法的混合体。
