The OnClientReordering event is fired just before the drag-to-reorder operation is completed and the dragged tab is still in its initial position.
This event will be fired only when the EnableDragToReorder property is set to "true"
The event handler function receives two parameters:
The instance of the tabstrip firing the event.
An eventArgs parameter containing the following methods:
get_tab returns a reference to the RadTab which has been dragged.
get_index returns the zero-based index where the dragged tab will be inserted in the tabs collection once dropped.
get_offset returns the offset between the index of the dragged tab before the drag operation and the one where it's about to be dropped.
get_domEvent returns a reference to the DOM event object for the action that caused this event to be fired.
set_cancel lets you stop the reorder operation by passing boolen value as a parameter. This will leave the dragged tab in its initial position.