public void TreeViewExpandNode(HttpContext context) { // Get the path to the tree view node // from the http request's parameters. string path = context.Request.Params["Path"]; // Get the id of the tree view // from the http request's paramters. string idTreeView = context.Request.Params["IdTreeView"]; if (HttpContext.Current.Session["TreeView" + idTreeView] == null) { return; } TreeView treeView = (TreeView)HttpContext.Current.Session["TreeView" + idTreeView]; TreeViewNode node = treeView.Select(path); if (node == null) { return; } node.Expanded = true; Panel pnlChildNodes = node.RenderChildNodes(true); context.Response.Write(pnlChildNodes.ToHtml()); }