C#

<?xml version="1.0" encoding="utf-8" ?>
<categories>
	<categorie>ASP</categorie>
		<sniplet>
			<name>1st Sniplet</name>
			<code>Response.Write "Hello World!"</code>
		</sniplet>
</categories>

    TreeNode treeRoot = new TreeNode();
    treeRoot.ImageIndex = 0;
    treeRoot.Text = "Code Samples ";
    XmlDocument xmlDoc = new XmlDocument();
    xmlDoc.Load(Application.StartupPath  + @"\XMLTree.xml");
    try
    {
        XmlNodeList xmlnodeList, subNodeList;
        XmlElement rootNode = xmlDoc.DocumentElement;
        xmlnodeList = rootNode.SelectNodes("categorie");
        elements = xmlnodeList.Count;

        foreach(XmlNode x in xmlnodeList)
        {
            TreeNode treeNode = new TreeNode();
            treeNode.ImageIndex = 1;
            treeNode.Text = x.InnerText;

            //look for listing in particular section...
            if(x.HasChildNodes)
            {
                subNodeList = x.SelectNodes("sniplet");

                                        // this didn't do what I thought it would.
                                        //subNodeList = x.ChildNodes;

                foreach(XmlNode sub in subNodeList)
                {
                    TreeNode subtree = new TreeNode();
                    subtree.Text = sub.InnerText;
                    treeNode.Nodes.Add(subtree);
                }
            }

            treeRoot.Nodes.Add(treeNode);
        }
    }
    catch(XmlException e)
    {
        MessageBox.Show(e.Message + "\n\n" + e.StackTrace);
    }

    treeRoot.ExpandAll();
    this.treeView1.Nodes.Add(treeRoot);
}