Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        AddItemToListBox1(Me.TextBox1.Text)
        AddItemToListBox2(Me.TextBox1.Text)

    End Sub

    Sub AddItemToListBox1(ByVal nItem As Integer)

        For i As Integer = 0 To nItem
            Me.ListBox1.Items.Add("Item " & i)
        Next

    End Sub

    Sub AddItemToListBox2(ByVal nItem As Integer)

        For i As Integer = 0 To nItem * 2
            Me.ListBox2.Items.Add("Item " & i)
        Next

    End Sub