String to String XML pretty Printer in C#

XmlPrettyPrint.cs

        public string PrettyPrint(string xml)
        {
            XmlDocument doc = new XmlDocument();
            doc.LoadXml(xml);
            var sb = new StringBuilder();
            var sw = new StringWriter(sb);
            var xw = new XmlTextWriter(sw);
            xw.Formatting = Formatting.Indented;
            doc.WriteTo(xw);
            return sb.ToString();
        }