How to get the values of 'param: optionStr' ,using insertNew

using insertNewNext,a new node was created, but how to get the values of ‘param: optionStr’

tree.insertNewNext(“db_5”, “kkk”, “kkk”, 0,0,0,“fffffff”,“”)

I think this document will helps you:
docs.dhtmlx.com/doku.php?id=dhtm … nipulation