Imports System

Imports System.Collections.Generic

Imports System.Linq

Public Module Module1

    Public Class Data

        Public ColumnList As New List(Of Column)()

        Public RowList As New List(Of Row)()

    End Class

    Public Class Row

        Public CellList As New List(Of Cell)()

    End Class

    Public Class Column

        Public name As String

    End Class

    Public Class Cell

        Public value As Object

        Public col As Column

    End Class

​

    Public Sub Main()

        Dim data = New Data()

        data.ColumnList.Add(New Column() With {.name = "FieldA"})

        data.ColumnList.Add(New Column() With {.name = "FieldB"})

        Dim row = New Row()

        row.CellList.Add(New Cell() With {.value = 1, .col = data.ColumnList(0)})

        row.CellList.Add(New Cell() With {.value = 2, .col = data.ColumnList(1)})

        data.RowList.Add(row)

        row = New Row()

        row.CellList.Add(New Cell() With {.value = 34, .col = data.ColumnList(0)})

        row.CellList.Add(New Cell() With {.value = 2, .col = data.ColumnList(1)})

        data.RowList.Add(row)

​

        Console.WriteLine(IsPK_CustomData(data, New String() {"FieldB"}))

        Console.WriteLine(IsPK_CustomData(data, New String() {"FieldA", "FieldB"}))

    End Sub

​

    Private Function IsPK_CustomData(data As Data, ParamArray fields As String()) As Boolean

        Dim keyValues = data.RowList _

            .[Select](Function(r) r.CellList.Where(Function(c) fields.Contains(c.col.name)) _

            .[Select](Function(c) c.value).ToArray()).ToArray()

        For i As Integer = 1 To keyValues.Length - 1

            For j As Integer = i - 1 To 0 Step -1

                If keyValues(i).SequenceEqual(keyValues(j)) Then

                    Return False

                End If

            Next

        Next

        Return True

    End Function

End Module