NodePopulating プロパティ

// The client event 'NodePopulating' takes two parameters sender and e
// sender  is the object which is raising the event
// e is the DataTreeNodeEventArgs
function WebDataTree_NodePopulating(sender, e) {

    //Gets the node object that is populating
    var node = e.getNode();

    //Gets the text of the node
    var nodeText = node.get_text();

     if (!confirm("Are you sure you want to populate the node '" + nodeText + "'?"))
    //Cancels the NodePopulating event
       e.set_cancel(true);


}