or

function
OnClientBlurHandler(sender, eventArgs) {
var item = sender.findItemByText(sender.get_text());
if (!item) {
debugger;
sender.clearSelection();
sender.clearItems();
var comboItem = new Telerik.Web.UI.RadComboBoxItem();
comboItem.set_text(
"Blanck");
sender.get_items().add(comboItem);
sender.commitChanges();
sleep(10000);
alert(sender.get_text());
sender._filter = 0;
}
}


<telerik:GridAttachmentColumn ButtonType="ImageButton" ImageUrl="~/Images/pdf_icon.gif" DataSourceID="odsLetter" HeaderImageUrl="~/Images/pdf_icon.gif" HeaderTooltip="Download Letter"DataTextField="FileName" AllowFiltering="false" AttachmentDataField="FileBLOB" AttachmentKeyFields="HTC_Key" FileNameTextField="FileName" UniqueName="Letter" SortExpression="LetterReleased"> <HeaderStyle HorizontalAlign="Center" /> <ItemStyle HorizontalAlign="Center" /> </telerik:GridAttachmentColumn><telerik:RadCodeBlock ID="RadCodeBlock2" runat="server"> <script type="text/javascript"><!-- function gridCommand(sender, args) { if (args.get_commandName() == "DownloadAttachment") { var manager = $find('<%= RadAjaxManager.GetCurrent(Page).ClientID %>'); manager.set_enableAJAX(false); setTimeout(function () { manager.set_enableAJAX(true); }, 0); } } --> </script></telerik:RadCodeBlock>