Save to XML from TreeView

[Nessa]

I have a problem with saving my data from \[code\]TreeView\[/code\]. I've googled a lot of topics how to save data from \[code\]TreeView\[/code\] to \[code\]XML\[/code\], and I saw i few methods how to make that. But all of them were using \[code\]WindowsForms application\[/code\], and nobody - \[code\]WPF\[/code\]. I tried to convert those examples to \[code\]WPF\[/code\], but no one from them do not work correct. Is there any way to make it? One of the ways I tried to port:\[code\] void SaveToXml(TreeView tw) { XmlDocument d = new XmlDocument(); XmlNode n = d.CreateNode(XmlNodeType.Element, "root", ""); foreach (TreeViewItem t in tw.Items) { n.AppendChild(getXmlNode(t, d)); } d.AppendChild(n); d.Save(AppDomain.CurrentDomain.BaseDirectory + "out.xml"); } private XmlNode getXmlNode(TreeViewItem tnode, XmlDocument d) { XmlNode n = d.CreateNode(XmlNodeType.Element, tnode.Name, " "); foreach (TreeViewItem t in tnode.Items) { n.AppendChild(getXmlNode(t, d)); } return n; }\[/code\]It throws \[code\]ArgumentException\[/code\] "Local element's and attribute's names cannot be empty". I'm trying to save info about files on my \[code\]D:\\[/code\] drive using code: \[code\] private void ListDirectory(TreeView treeView, string path) { var rootDirectoryInfo = new DirectoryInfo(path); treeView.Items.Add(CreateDirectoryNode(rootDirectoryInfo)); } private static TreeViewItem CreateDirectoryNode(DirectoryInfo directoryInfo) { var directoryNode = new TreeViewItem(); directoryNode.Header = directoryInfo.Name; try { foreach (var directory in directoryInfo.GetDirectories()) directoryNode.Items.Add(CreateDirectoryNode(directory)); foreach (var file in directoryInfo.GetFiles()) directoryNode.Items.Add(new TreeViewItem { Header = file.Name }); } catch (UnauthorizedAccessException e) { } return directoryNode; }\[/code\]It works fine, and \[code\]TreeView\[/code\] shows all the folders and files. Please, show me how to save data from \[code\]TreeView\[/code\] to \[code\]XML\[/code\]. Thanks.Tried this:\[code\] public void exportToXml(TreeView tv, string filename) { sr = new StreamWriter(filename, false, System.Text.Encoding.UTF8); //Write the header sr.WriteLine("<?xml version=\"1.0\" encoding=\"utf-8\" ?>"); //Write our root node sr.WriteLine("<ROOT>"); foreach (TreeViewItem node in tv.Items) { saveNode(node.Items); } //Close the root node sr.WriteLine("</ROOT>"); sr.Close(); } private void saveNode(TreeViewItem[] tnc) { foreach (TreeViewItem node in tnc) { //If we have child nodes, we'll write //a parent node, then iterrate through //the children if (node.Items.Count > 0) { sr.WriteLine("<" + node.Name + ">"); saveNode(node.Items); sr.WriteLine("</" + node.Name + ">"); } else //No child nodes, so we just write the text sr.WriteLine(node.Name); } }\[/code\]But \[code\]saveNode(node.Items);\[/code\] says that there are different types between \[code\]node.Items\[/code\] and \[code\]TreeViewItem[]\[/code\], so I tried \[code\]List<TreeViewItem>\[/code\], but error is the same.