Why is chevron being encoded differently when I use XmlTextWriter class?

Question

Seem to have some funny behaviour going on when I call the XMLTextWriter...

XmlTextWriter writer = new XmlTextWriter(targetFileName, Encoding.UTF8);

writer.WriteValue("< ?xml version=\"1.0\" encoding=\"UTF-8\"?>");
writer.WriteString(Environment.NewLine);
writer.WriteStartElement("video","UploadXsd");
writer.WriteString(Environment.NewLine);
    writer.WriteStartElement("title");
        writer.WriteString(Environment.NewLine);
        writer.WriteString(title);
        writer.WriteString(Environment.NewLine);
    writer.WriteEndElement();
    writer.WriteString(Environment.NewLine);
    writer.WriteStartElement("description");
    writer.WriteString(Environment.NewLine);
        writer.WriteString(description);
        writer.WriteString(Environment.NewLine);
    writer.WriteEndElement();
    writer.WriteString(Environment.NewLine);
    writer.WriteStartElement("contributor");
    writer.WriteString(Environment.NewLine);
        writer.WriteString(contributor);
        writer.WriteString(Environment.NewLine);
    writer.WriteEndElement();
    writer.WriteString(Environment.NewLine);
    writer.WriteStartElement("subject");
    writer.WriteString(Environment.NewLine);
        writer.WriteString(subject);
        writer.WriteString(Environment.NewLine);
    writer.WriteEndElement();
    writer.WriteString(Environment.NewLine);
writer.WriteEndElement();
writer.WriteString(Environment.NewLine);

writer.Flush();
writer.Close();

Then I see that it is creating this:

&lt; ?xml version="1.0" encoding="UTF-8"?&gt;
<video xmlns="UploadXsd">
<title>
MyTitle
</title>
<description>
MyDescription
</description>
<contributor>
MyContributor
</contributor>
<subject>
MySubject
</subject>
</video>

Why has the writer encoded the first element into Html but not the rest?, and more to the point how do I stop it doing this? I just want to create the first element.

score 1 · Answer 1 · answered Jun 24 '11 at 11:30

1

Why has the writer encoded the first element into Html but not the rest?

Because it is the only place you used WriteValue

how do I stop it doing this? I just want to create the first element.

The XML declaration is not an element. It is a processing instruction. Since version 1.0 and a UTF-8 encoding is the default, the simplest thing to do is to just omit it entirely. It won't make a difference to the meaning of the document, but saves you time and a few bytes.

If you really want to include it, then use WriteStartDocument

answered Jun 24 '11 at 11:30

Quentin

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Cool, I have changed it to : writer.WriteRaw("< ?xml version=\"1.0\" encoding=\"UTF-8\"?>"); – Exitos Jun 24 '11 at 11:33
Actually the XML declaration is not a processing instruction either, but for the purpose of this API you can probably treat it as one. – Michael Kay Jun 24 '11 at 14:43

score 0 · Accepted Answer · answered Jun 24 '11 at 11:33

Do not use WriteValue() , it does the encoding. Use WriteProcessingInstruction instead.

MSDN example:

XmlWriter writer = XmlWriter.Create("output.xml");
writer.WriteProcessingInstruction("xml", "version='1.0' encoding='UTF-16'");
writer.WriteStartElement("root");
writer.Close();

Why is chevron being encoded differently when I use XmlTextWriter class?

2 Answers2