Hello Damien,

Thank you for contacting us.

If I understand you correctly, you would like to save the expanded node on expanding? To achieve such a functionality, you can use the NodeExpanded event and in the handler you can save the particular node like this:

nodeExpanded: function(evt, ui) {

            if (typeof(Storage) !== "undefined") {

              // Code for localStorage.

              var node = ui.node;

              //save

              localStorage.setItem("key", JSON.stringify(node));

              //retrieve

              var savedNode = localStorage.getItem("key");

                savedNode = JSON.parse(savedNode);

                //saved node

                $("#localStore").html(savedNode.data.RegionName);

              } else {

                // Sorry! No Web Storage support..

                alert("No localStorage support!");

              }

            }

Here is a corresponding sample. Please take a look at it and let me know if you have further questions.

http://jsfiddle.net/h1xeu8th/14/

Best Regards,
Marina Stoyanova,
Software Developer,
Infragistics, Inc.