Treeview: Set Style in code behind on certain conditons

After finishing all process, send the treeview to callrecursive function.hope it gives  an idea

////Call the Callrecursive function       

private void PrintRecursive(TreeNode treeNode)
        {
            try
            {
                // Print each node recursively.      
                foreach (TreeNode tn in treeNode.Nodes)
                {
                    if (//Condition to find your node)
                    {
                        //Change style

                    }
                    PrintRecursive(tn);
                }
            }
            catch(Exception ex)
            {
                throw ex;
            }
        }    
        // Call the procedure using the TreeView.
        private void CallRecursive(TreeView treeView)
        {     
            TreeNodeCollection nodes = treeView.Nodes;
            foreach (TreeNode n in nodes)
            {
                PrintRecursive(n);
            }
        }