Calendar control with date range.

Here is the code for calendar control which is for only feature date. you can not select the old date so you can not set any validation for old date.

<asp:TextBox ID="txt_date2" runat="server"></asp:TextBox>
        <cc1:CalendarExtender ID="CalendarExtender2" runat="server" TargetControlID="txt_date2" PopupPosition="Right" Format="dd/MM/yyyy" >
        </cc1:CalendarExtender>

    protected void Page_Load(object sender, EventArgs e)
    {
          CalendarExtender2.StartDate = DateTime.Now;
    }