IE8 script error when selecting > 800 rows in radlistbox

[Tony]

Hello,

I currently have a radlistbox that is fully populated.  The sectionmode is set to Multiple.  When I try to select more than 800 rows I get the following error: Stop running this script?  A script on this page is causing your web browser to run slowly.  If it continues to run, your computer might become unresponsive."  in IE8 (works in IE9)

I have two listbox which I'm transferring rows between (which works fine).  The issue is with the browser/client trying to highlight/select multiple rows.  For testing purposes I set the listbox to AutoPostBack.  I noticed "SelectedIndexChanged" get's fired on the first click.  Then I Shift-click the last row and I get the above error message before it post back to the server (indicating it's the client side that's failing)

 

<telerik:RadListBox ID="lbCostCentre" runat="server" Height="550px"
             Width="270px" AllowTransfer="True" AllowTransferOnDoubleClick="True"
             AutoPostBackOnDelete="True" AutoPostBackOnTransfer="True"
             EnableDragAndDrop="True" SelectionMode="Multiple"
             TransferToID="lbAssignedCostCentre" AutoPostBack="True"
         EnableTheming="False">
         <ButtonSettings TransferButtons="Common" ShowTransferAll="False">
         </ButtonSettings>
     </telerik:RadListBox>

[Dimitar Terziev]

Hi Tony,

When such amount of items is being selected a certain java-script operation is performed for each of these items which may result in such error in older browsers like IE8 which is known for its poor performance in terms of java-script execution. Currently there is not much that we could do to optimize the control in order to deal with this browser limitation.

All the best,
Dimitar Terziev
the Telerik team