RadTreeView provides a rich client-side API and event model.

1.       You can obtain the reference to the client-side object of RadTreeView using the following javascript:

var tree = <%=RadTree1.ClientID%>

2.       Once you get the client-side object, you can use various methods and properties to manipulate it. More information about RadTreeView client-side object model you can find in the help files - Client-Side Object Model