<!DOCTYPE html>
<html>
<head>
<script  language="VB" runat="server">
Sub Change(obj As Object, e As EventArgs)
      Response.Write("Date: ")
      Response.Write(cal1.SelectedDate.ToShortDateString())
End Sub
</script>

</head>

<body>
<form runat="server">
<asp:Calendar id="cal1" runat="server" OnSelectionChanged="Change" />
</form>
</body>
</html>