Public Class Form1
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        For i As Int32 = 1 To 9
            ListBox1.Items.Add((i * 1000).ToString)
        Next
    End Sub
 
    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e _
      As System.EventArgs) Handles ListBox1.SelectedIndexChanged
        TextBox1.Text = ListBox1.SelectedItem
    End Sub
End Class