Error: The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>)

if application throw the following error,Place the script with in the body.


Error:

The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>). 

Maintain Scrollbar Position Inside UpdatePanel After Partial PostBack

<asp:ScriptManager ID="tsm" runat="server" ScriptMode="Release" />

            <script type="text/javascript">
             
                var xPos, yPos;
                var prm = Sys.WebForms.PageRequestManager.getInstance();
                function BeginRequestHandler(sender, args) {
                    if ($get('<%=Panel1.ClientID%>') != null) {
                        xPos = $get('<%=Panel1.ClientID %>').scrollLeft;
                        yPos = $get('<%=Panel1.ClientID %>').scrollTop;
                    }
                }

                function EndRequestHandler(sender, args) {
                    if ($get('<%=Panel1.ClientID%>') != null) {
                        $get('<%=Panel1.ClientID%>').scrollLeft = xPos;
                        $get('<%=Panel1.ClientID%>').scrollTop = yPos;

                    }
                }

                prm.add_beginRequest(BeginRequestHandler);
                prm.add_endRequest(EndRequestHandler);
            </script>

Reference:
http://basgun.wordpress.com/2008/06/09/maintain-scroll-position-updatepanel-postback/

Note:

if application throw the following error,Place the script with in the body.

Error:

The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).