主题：筛选问题

Dim idxs As String = "'',"
Dim pdr As DataRow = Nothing
Dim count As Integer = 0
Dim cs As String = "第一列,第二列"
For Each dr As DataRow In DataTables("表A").Select("", cs)
    Dim flag As Boolean = False
    If pdr IsNot Nothing Then
        If dr("第一列") <> pdr("第一列") Then
            flag = True
        End If
        If flag Then
            count = 1
        Else
            If dr("第二列") <> pdr("第二列") Then
                count += 1
                If count = 2 Then
                    idxs &= "'" & dr("第一列") & "',"
                End If
            End If
        End If
    Else
        count += 1
    End If
    pdr = dr
Next