linq to DataTable group by用法(VB.Net语法)

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Module Module1    Sub Main()        Dim table As New DataTable        table.Columns.Add("A", GetType(Integer))        table.Columns.Add("B", GetType(Integer))        table.Columns.Add("C", GetType(Integer))        table.Columns.Add("S", GetType(Integer))        table.Columns.Add("S1", GetType(Integer))        table.Columns.Add("S2", GetType(Integer))        table.Rows.Add(1, 1, 1, 1, 1, 1)        table.Rows.Add(1, 1, 1, 2, 1, 1)        table.Rows.Add(1, 1, 2, 3, 2, DBNull.Value)        table.Rows.Add(1, 1, 2, 4, 2, 1)        table.Rows.Add(1, 1, 3, 5, DBNull.Value, 1)        table.Rows.Add(2, 1, 3, 6, 3, 1)        table.Rows.Add(2, 1, 3, 7, 3, 1)        table.Rows.Add(2, 1, 4, 8, 4, 1)        table.Rows.Add(2, 1, 4, 9, 4, 1)        table.Rows.Add(2, DBNull.Value, 4, DBNull.Value)        table.Rows.Add(2, DBNull.Value, 4, 11)        Dim temp = From p In table.AsEnumerable                                    Group p By Key = New With {Key .A = p("A"), Key .B = p("B"), Key .C = p("C")} Into g = Group                                    Select New With {                                        .key = Key, _                                        .Suryo1 = g.Sum(Function(x) If(IsDBNull(x("S")), 0, x("S")))                                    }        Dim a = temp.ToList()        Dim s = ""    End SubEnd Module

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