public static void LoadExpenses(TreeListView lView, string xFile) { Throw.IfFalse(File.Exists(xFile), new FileNotFoundException(xFile)); InitializeListView(lView); var xDoc = XDocument.Load(xFile); Debug.Assert(xDoc.Root.Name == "Expenses"); Debug.Assert(xDoc.Root.Attributes().Count() >= 2); var xList = new List <XElement>(xDoc.Root.Elements()); var lItems = PrepareTree(xList, null); foreach (var li in lItems) { lView.AddItem(li); } }