public static void addExtraFileReferencesToTreeNode(TreeNode treeNode, string file) { if (treeNode != null && File.Exists(file)) { treeNode.Nodes.Clear(); // this will get the list of files to compile (which includes the extra files referenced in the source code that we want to add to this treeview) var filesToCompile = new List <string>(); filesToCompile.Add(file); CompileEngine.addSourceFileOrFolderIncludedInSourceCode(filesToCompile, new List <string>(), new List <string>()); filesToCompile.Remove(file); foreach (var extraFile in filesToCompile) { O2Forms.newTreeNode(treeNode, Path.GetFileName(extraFile), 5, extraFile); } treeNode.ExpandAll(); } }