FairyGUI.TreeView.CollapseAll C# (CSharp) Method

        public void CollapseAll(TreeNode folderNode)
        {
            if (folderNode != root)
                folderNode.expanded = false;
            int cnt = folderNode.numChildren;
            for (int i = 0; i < cnt; i++)
            {
                TreeNode node = folderNode.GetChildAt(i);
                if (node.isFolder)
                    CollapseAll(node);
            }
        }

 static public int CollapseAll(IntPtr l)
 {
     try {
         FairyGUI.TreeView self = (FairyGUI.TreeView)checkSelf(l);
         FairyGUI.TreeNode a1;
         checkType(l, 2, out a1);
         self.CollapseAll(a1);
         pushValue(l, true);
         return(1);
     }
     catch (Exception e) {
         return(error(l, e));
     }
 }