Serialize with an XML declaration (LINQ to XML)

This article describes how to control whether an XML declaration is generated when you serialize XML in C# or Visual Basic.

Serializing to a File or a TextWriter using the XElement.Save method or the XDocument.Save method generates an XML declaration. When you serialize to an XmlWriter, the writer settings (specified in an XmlWriterSettings object) determine whether an XML declaration is generated.

If you're serializing to a string using the ToString method, the resulting XML won't include an XML declaration.

Example: Serialize with an XML declaration

The following example creates an XElement, saves the document to a file, and then prints the file to the console:

XElement root = new XElement("Root",
    new XElement("Child", "child content")
);
root.Save("Root.xml");
string str = File.ReadAllText("Root.xml");
Console.WriteLine(str);
Dim root As XElement = <Root>
                           <Child>child content</Child>
                       </Root>
root.Save("Root.xml")
Dim str As String = File.ReadAllText("Root.xml")
Console.WriteLine(str)

This example produces the following output:

<?xml version="1.0" encoding="utf-8"?>
<Root>
  <Child>child content</Child>
</Root>

Example: Serialize without an XML declaration

The following example shows how to save an XElement to an XmlWriter.

StringBuilder sb = new StringBuilder();
XmlWriterSettings xws = new XmlWriterSettings();
xws.OmitXmlDeclaration = true;

using (XmlWriter xw = XmlWriter.Create(sb, xws)) {
    XElement root = new XElement("Root",
        new XElement("Child", "child content")
    );
    root.Save(xw);
}
Console.WriteLine(sb.ToString());
Dim sb As StringBuilder = New StringBuilder()
Dim xws As XmlWriterSettings = New XmlWriterSettings()
xws.OmitXmlDeclaration = True

Using xw As XmlWriter = XmlWriter.Create(sb, xws)
    Dim root = <Root>
                   <Child>child content</Child>
               </Root>
    root.Save(xw)
End Using
Console.WriteLine(sb.ToString())

This example produces the following output:

<Root><Child>child content</Child></Root>