Control ListBox: Método de Burbuja - Visual Basic 2012

Public Class Form1

    Private Sub btnAdd_Click(sender As Object, e As EventArgs) Handles btnAdd.Click
        ListBox1.Items.Add(txtNumero.Text)
        txtNumero.Clear()
        txtNumero.Focus()
    End Sub

    Private Sub btnOrdenar_Click(sender As Object, e As EventArgs) Handles btnOrdenar.Click
        Dim Auxiliar As Integer
        For i = 0 To ListBox1.Items.Count - 1
            For j = 0 To ListBox1.Items.Count - 2
                If (ListBox1.Items.Item(j) > ListBox1.Items.Item(i)) Then
                    Auxiliar = ListBox1.Items.Item(j)
                    ListBox1.Items.Item(j) = ListBox1.Items.Item(i)
                    ListBox1.Items.Item(i) = Auxiliar
                End If
            Next
        Next
    End Sub
End Class

Video Tuturial - Método de Burbuja en Visual Basic 2012