RadTreeView NodeExpand

[sudesh]

Hello,

I have used RadTreeView control in a ASP.net page and below code will add nodes  to the tree considering whether there should be child nodes.
              
               if (childNodes.Count() > 0)
                    {
                        node.ExpandMode = TreeNodeExpandMode.ServerSideCallBack;
                    }                                   
 
                    treeViewControl.Nodes[0].Nodes.Add(node);    

The nodeExpand method will load the child nodes for a particular node when it is clicked.

When a node is expanded a serverSide postbak happens and so that the member variables in the class is re-initialized. Is there a way that i can avoid this?
I need to keep a variable value through out the node expandings till a page closes.

Thanks,
Sudesh