主题：自定义函数有误,如何修改？

Dim kms() As String = Args(0)

Dim pm As List(Of String()) = CurrentTable.DataTable.GetValues("年级|选做","")

Dim pmc As Integer

Dim TotalName As String

CurrentTable.Redraw = False

For Each km As String In kms

    For i As Integer = 0 To pm.Count -1

        If pm(i)(0) = "" Then

            Continue For

        End If

        Dim drs As List(Of DataRow) = CurrentTable.DataTable.Select("[年级] = '" & pm(i)(0) & "'And [选做] = '" & pm(i)(1) &  "'", km & " DESC") '字符型

        pmc = 0

        TotalName = km & "名次"

        For n As Integer = 0 To drs.Count - 1

            pmc = pmc +1

            If n > 0 AndAlso drs(n)(km ) = drs(n-1)(km) Then

                drs(n)(TotalName ) = drs(n-1)(TotalName )

            Else

                drs(n)(TotalName ) = pmc

            End If

        Next

    Next

Next

CurrentTable.Redraw = True