Protected Sub ListView1_ItemCreated(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.ListViewItemEventArgs) Handles ListView1.ItemCreated
  Dim lw As ListView = DirectCast(sender, ListView)
  Dim li As ListViewItem = e.Item

  If li.ItemType = ListViewItemType.InsertItem Then
    'valore predefinito campo data_ora = data corrente
    Dim data_ora As TextBox = DirectCast(li.FindControl("data_ora"), TextBox)
    If data_ora IsNot Nothing Then
      data_ora.Text = DateTime.Today.ToShortDateString
    End If

  End If

End Sub