This event calls user-defined handlers (if there are any) and passes the following parameters:

• sId - id of the source item (id after inserting into the tree, my not be equal to the initial id);
• tId - id of the target item;
• id - if the node is dropped as a sibling, id of the item before which the source node will be inserted;
• sObject - source tree object;
• tObject - target tree object.

           tree.attachEvent("onDrop", function(sId,tId,id,sObject,tObject){});