<!DOCTYPE html>
<html>
<head>
<script runat="server">
Sub Change(obj As Object, e As EventArgs)
Dim i As Integer
For i = 0 To Cal1.SelectedDates.Count - 1
Response.Write(Cal1.SelectedDates(i).ToShortDateString())
Response.Write("<br>")
Next i
End Sub
</script>
</head>
<body>
<form runat="server">
<asp:Calendar ID="Cal1" runat="server" SelectionMode="DayWeekMonth" OnSelectionChanged="Change" />
</form>
</body>
</html>