Private Function TestaCPF(CPF As String) As String
        Dim dadosArray() As String = {"11111111111", "22222222222", "33333333333", "44444444444", "55555555555", "66666666666", "77777777777", "88888888888", "99999999999"}
        Dim vResultado As Boolean = True
        Dim i, x, n1, n2 As Integer
        CPF = CPF.Trim
        For i = 0 To dadosArray.Length - 1
            If CPF.Length <> 11 Or dadosArray(i).Equals(CPF) Then
                vResultado = False
            End If
        Next
        If vResultado = False Then
            Return "00000000000"
        Else
            For x = 0 To 1
                n1 = 0
                For i = 0 To 8 + x
                    n1 = n1 + Val(CPF.Substring(i, 1)) * (10 + x - i)
                Next
                n2 = 11 - (n1 - (Int(n1 / 11) * 11))
                If n2 = 10 Or n2 = 11 Then n2 = 0
                If n2 <> Val(CPF.Substring(9 + x, 1)) Then
                    vResultado = False
                    Exit For
                End If
            Next
            If vResultado = False Then
                Return "00000000000"
            End If
        End If
        Return CPF
End Function