Question

            Person person = GetPerson();
            XmlSerializerNamespaces ns = new XmlSerializerNamespaces();
            ns.Add(string.Empty, string.Empty);
            XmlSerializer serializer = new XmlSerializer(typeof(Person));
            string personText = string.Empty;
            using (MemoryStream memoryStream = new MemoryStream())
            {
                using (XmlWriter xmlWriter = XmlWriter.Create(memoryStream, new XmlWriterSettings() { Encoding = Encoding.UTF8 }))
                {
                    serializer.Serialize(xmlWriter, person, ns);
                    xmlWriter.Flush();
                    personText = Encoding.UTF8.GetString(memoryStream.ToArray());
                }
            }

            string path = @"D:\person.xml";
// Write method 1:
            File.WriteAllText(path, personText);

// Write method 2:
            using (StreamWriter streamWriter = new StreamWriter(path, false , Encoding.UTF8))
            {
                streamWriter.Write(personText);
            }

// Read the xml
            using (FileStream fileStream = new FileStream(path, FileMode.Open))
            {
                return XDocument.Load(XmlReader.Create(fileStream));
            }

When I read the xml after writing using method 2, I get this Data at the root level is invalid. Line 1, position 1. But it works fine using method 1.

What is causing this? Any pointers appreciated.

Answer 1

The problem is that both the StreamWriter and the XmlWriter are adding a byte-order-mark.

Options:

• String the BOM from personText to start with
• Pass new UTF8Encoding(false) instead of Encoding.UTF8 for the StreamWriter
• Pass new UTF8Encoding(false) instead of Encoding.UTF8 for the XmlWriter
• Avoid converting to text and back again in the first place: you’ve got the binary data in the MemoryStream, why not just dump that to disk?