Question

XDocument xDocumentObject = XDocument.Parse("<Test>"+
            "<elementx id='1'  att='aaa' />" +
            "<elementx id='2'  att='bbb' />" +
            "</Test>");

What is the difference between :

1)

byte[] xmlBytes = Encoding.Default.GetBytes(xDocumentObject.ToString());

AND

2)

byte[] xmlBytes;
using (MemoryStream ms = new MemoryStream())
{
   xDocumentObject.Save(ms);
   xmlBytes = ms.ToArray();
}

What is “Default” encoding in (1) and what is the encoding used in (2) and which is the preferred way?

Answer 1

In the first case you are using the encoding for the operating system’s current ANSI code page to convert the string to a byte array. The string represents the XML document generated by the XDocument instance and converted to a byte array. In .NET all strings are Unicode encoded.

In the second example the encoding of the XDocument is used. So for example if you have the following XML <?xml encoding="utf-8"?> it will use UTF-8. The Declaration property allows you to specify the encoding being used:

XDocument xDocumentObject = new XDocument(
    new XDeclaration("1.0", "utf-8", "yes"), 
    new XElement(
        "Test",
        new XElement("elementx", new XAttribute("id", "1"), new XAttribute("att", "aaa")), 
        new XElement("elementx", new XAttribute("id", "2"), new XAttribute("att", "bbb"))
    )
);

or:

XDocument xDocumentObject = XDocument.Parse(
    @"<?xml version=""1.0"" encoding=""utf-8"" standalone=""yes""?>
    <Test>
        <elementx id=""1"" att=""aaa"" />
        <elementx id=""2"" att=""bbb"" />
    </Test>"
);

allows you to specify UTF-8 encoding.