Novacode.DocX.AddHeadersOrFooters C# (CSharp) Method

        internal void AddHeadersOrFooters(bool b)
        {
            string element = "ftr";
            string reference = "footer";
            if (b)
            {
                element = "hdr";
                reference = "header";
            }

            DeleteHeadersOrFooters(b);

            XElement sectPr = mainDoc.Root.Element(w + "body").Element(w + "sectPr");

            for (int i = 1; i < 4; i++)
            {
                string header_uri = string.Format("/word/{0}{1}.xml", reference, i);

                PackagePart headerPart = package.CreatePart(new Uri(header_uri, UriKind.Relative), string.Format("application/vnd.openxmlformats-officedocument.wordprocessingml.{0}+xml", reference), CompressionOption.Normal);
                PackageRelationship headerRelationship = mainPart.CreateRelationship(headerPart.Uri, TargetMode.Internal, string.Format("http://schemas.openxmlformats.org/officeDocument/2006/relationships/{0}", reference));

                XDocument header;

                // Load the document part into a XDocument object
                using (TextReader tr = new StreamReader(headerPart.GetStream(FileMode.Create, FileAccess.ReadWrite)))
                {
                    header = XDocument.Parse
                    (string.Format(@"<?xml version=""1.0"" encoding=""utf-16"" standalone=""yes""?>
                       <w:{0} xmlns:ve=""http://schemas.openxmlformats.org/markup-compatibility/2006"" xmlns:o=""urn:schemas-microsoft-com:office:office"" xmlns:r=""http://schemas.openxmlformats.org/officeDocument/2006/relationships"" xmlns:m=""http://schemas.openxmlformats.org/officeDocument/2006/math"" xmlns:v=""urn:schemas-microsoft-com:vml"" xmlns:wp=""http://schemas.openxmlformats.org/drawingml/2006/wordprocessingDrawing"" xmlns:w10=""urn:schemas-microsoft-com:office:word"" xmlns:w=""http://schemas.openxmlformats.org/wordprocessingml/2006/main"" xmlns:wne=""http://schemas.microsoft.com/office/word/2006/wordml"">
                         <w:p w:rsidR=""009D472B"" w:rsidRDefault=""009D472B"">
                           <w:pPr>
                             <w:pStyle w:val=""{1}"" />
                           </w:pPr>
                         </w:p>
                       </w:{0}>", element, reference)
                    );
                }

                // Save the main document
                using (TextWriter tw = new StreamWriter(new PackagePartStream(headerPart.GetStream(FileMode.Create, FileAccess.Write))))
                    header.Save(tw, SaveOptions.None);

                string type;
                switch (i)
                {
                    case 1: type = "default"; break;
                    case 2: type = "even"; break;
                    case 3: type = "first"; break;
                    default: throw new ArgumentOutOfRangeException();
                }

                sectPr.Add
                (
                    new XElement
                    (
                        w + string.Format("{0}Reference", reference),
                        new XAttribute(w + "type", type),
                        new XAttribute(r + "id", headerRelationship.Id)
                    )
                );
            }
        }