c# - Writing in xml does not keep the formatting?

Question

I have this string :

<test>I am a test</test>

But when I write it in my xml file, and open it, I have this :

<test>I am a test</test>

I don't know how to use the good formatting. I tried HttpUtility.HtmlDecode, but it does not solve my problem.

Do you have an idea on this ?

Edit : Sorry for not having posted my code before, I thought my problem was really really trivial. Here is a sample I just wrote that resumes the situation (I'm not at work anymore so I don't have the original code) :

XmlDocument xmlDoc = new XmlDocument();
doc.LoadXml("<root>" +
            "<test>I am a test</test>" +
            "</root>");
string content = xmlDoc.DocumentElement.FirstChild.InnerXml;

XDocument saveFile = new XDocument();
saveFile = new XDocument(new XElement("settings", content));
saveFile.Save("myFile.xml");

I just want my xml file content looks like my original string, so in my case the file would normally contain :

<settings>
    <root>
        <test>I am a test</test>
    </root>
</settings>

Right ? But instead, I have something like :

<settings>&lt;root&gt;&lt;test&gt;I am a test&lt;/test&gt;&lt;/root&gt;
</settings>

Answer 1

You can do something along the lines of Converting XDocument to XmlDocument and vice versa to convert the root element of your XmlDocument to an XElement and then add it to your XDocument:

public static class XmlDocumentExtensions
{
    public static XElement ToXElement(this XmlDocument xmlDocument)
    {
        if (xmlDocument == null)
            throw new ArgumentNullException("xmlDocument");

        if (xmlDocument.DocumentElement == null)
            return null;

        using (var nodeReader = new XmlNodeReader(xmlDocument.DocumentElement))
        {
            return XElement.Load(nodeReader);
        }
    }        
}

And then use as follows:

        // Get legacy XmlDocument
        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml("<root>" +
                    "<test>I am a test</test>" +
                    "</root>");

        // Add its root element to the XDocument
        XDocument saveFile = new XDocument(
            new XElement("settings", xmlDoc.ToXElement()));

        // Save
        Debug.WriteLine(saveFile.ToString());

And the output is:

<settings>
  <root>
    <test>I am a test</test>
  </root>
</settings>

Note this avoids the overhead of converting the XmlDocument to an XML string and re-parsing it from scratch.