CalendarExtender

<asp:ScriptManager ID="ScriptManager1" runat="server">
    </asp:ScriptManager>
  
         
        <asp:UpdatePanel ID="UpdatePanel1" runat="server">
            <ContentTemplate>
                DateOne:<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
                DateTwo:<asp:TextBox ID="TextBox4" runat="server"></asp:TextBox>
                <asp:Image ID="Image2" runat="server" ImageUrl="~/images/book_title.jpg" />
                <cc1:CalendarExtender ID="CalendarExtender1" TargetControlID="TextBox1" PopupPosition="BottomRight" PopupButtonID="Image2" runat="server">
                </cc1:CalendarExtender>
                <cc1:CalendarExtender ID="CalendarExtender3" TargetControlID="TextBox4" PopupPosition="BottomRight" PopupButtonID="Image1" runat="server">
                </cc1:CalendarExtender>
                <asp:Image ID="Image1" runat="server" ImageUrl="~/images/qx.jpg" />
            </ContentTemplate>
        
        </asp:UpdatePanel>