RadListBox supports a number of client-side events that let you customize the behavior of the listbox:

• OnClientLoad client-side event occurs after RadListBox has been fully initialized on the client-side.

• OnClientDeleting occurs before the items are deleted. This event can be cancelled.

• OnClientDeleted occurs after the items are deleted.

• OnClientDragStart occurs as the drag operation occurs. This event can be cancelled.

• OnClientDragging occurs while an item is being dragged. This event can be cancelled.

• OnClientDropping occurs before the items are dropped. The event can be cancelled.

• OnClientDropped occurs after the item/items are dropped.

• OnClientItemDoubleClicking occurs when the user double clicks the item using the mouse. The event can be cancelled.

• OnClientItemDoubleClicked occurs after the user double clicks the item using the mouse.

• OnClientItemChecking occurs when the user selects a checkbox using mouse or keyboard. The event can be cancelled.

• OnClientItemChecked occurs after the item has been checked.

• OnClientItemsRequesting occurs before the items are added to the listbox' Items collection.

• OnClientItemsRequested occurs after the load-on-demand mechanism has added new items to the listbox.

• OnClientItemsRequestFailed occurs when an error has occurred while loading elements using the load-on-demand mechanism.

• OnClientReordering client-side event occurs when the item or items are about to be reordered. This event can be cancelled.

• OnClientReordered client-side event occurs after the item or items have been reordered.

• OnClientTransferring client-side event occurs when the selected item is about to be transferred to the destination RadListBox. This event can be cancelled.

• OnClientTransferred client-side event occurs after the selected item has been transferred to the destination RadListBox.

• OnClientSelectedIndexChanging client-side event occurs when the selected item is about to be changed. This event can be cancelled.

• OnClientSelectedIndexChanged occurs after the selected item has been changed.

• OnClientTemplateDataBound occurs after the client template is bound and the binding expression are evaluated.

• OnClientMouseOverclient-side event occurs when the mouse cursor passes over an item.

• OnClientMouseOutclient-side event occurs just before the mouse passes out of an item.

• OnClientContextMenu client-side event occurs when a user right clicks over a listbox item

To subscribe to a client event just set the appropriate property to the name of the javascript function that will handle the event. The function always receives two parameters - a sender (RadListBox firing the event) and event arguments having different methods.

CopyASPX

<telerik:radlistbox id="RadListBox1" allowdelete="true" onclientdeleted="onClientDeletedHandler"
    runat="server"></telerik:radlistbox>

CopyJavaScript

function onClientDeletedHandler(sender, e) {
    alert("Successfully deleted: " + e.get_item().get_text());
}

There is a shorter way to handle a client-side event:

CopyASPX

<telerik:radlistbox id="RadListBox2" allowdelete="true" 
    onclientdeleted="(function(sender, e){ alert('Successfully deleted: ' + e.get_item().get_text()); })"
    runat="server">
</telerik:radlistbox>

Similarly, you can set the property in code behind:

CopyC#

     

RadListBox1.OnClientDeleted = "onClientDeletedHandler";