<%@ Page Language="VB" Debug="true" %>
<script language="VB" runat="server">
private void Page_Load(Object source, EventArgs e)
{
  if (isPostBack)
  {
    myLabel.Text = myCalendar.SelectedDate;
  }
}
</script>
<form runat="server">
<asp:Calendar id="myCalendar" runat="server"/>
</form>
<asp:label id="myLabel" runat="server"/>