public static XDocument AddElementsInItemGroup(this XDocument xml, List <string> items) { var itemGroup = xml.AddItemGroupBeforeElement(); foreach (var item in items) { var match = Regex.Match(item, @"<(\w+).*Include=("".*"")"); var itemType = (string)match.Groups[1].Value; var include = match.Groups[2].Value; XElement newItem = new XElement(itemType, new XAttribute("Include", include)); itemGroup.Add(newItem); } return(xml); }