Question

I’m using a simple XmlReader on the following file structure:

<application>
    <nodetitle permission="perm1">Some Dept</nodetitle>
    <project>Project A</project>
    <links>
        <link>
            <pagename>page1.aspx</pagename>
        </link>
        <link>
            <pagename permission="perm2">page2.aspx</pagename>
        </link>
        <link>
            <pagename>page3.aspx</pagename>
        </link>
    </links>
</application>

I’m rusty on the XML API and my problem is reading the sibling <link> elements in a single pass – my instinct is to look to create some kind of inner loop?

while (reader.Read())
{
    ...

    if ((reader.NodeType == XmlNodeType.Element) && (reader.Name == "links"))
    {
        // read all <link> elements in a single pass
    }
    ...
}

UPDATE – 06-25-2011

I’m going to try and be a little more specific. I’m not using XPath. Using either the XmlReader or Linq to Xml (am totally unfamiliar with this), I want a way to extract the link elements and attributes and check their values.

Answer 1

Well if you use an XML doc you could do something like this:

XmlNodeList nodeList = xmlDocument
    .DocumentElement.SelectNodes("//application/links/link");

foreach (XmlNode node in nodeList) {
    ...
}

In the loop just get the inner <pageName> element and read the attributes and/or text.

That said, XPath is much easier, faster and memory efficient than a reader or a full Xml doc. Linq2XML is also really good to work with, since you can use Linq syntax on the parse tree.

Edit:

I felt kind of dirty for mentioning XmlDocument so I created a simple Linq2Xml example to show how easy this is even omitting any Linq syntax, just in case you want to go for it:

string path = @"C:\path\to\my\xmlfile.xml";
XDocument doc = XDocument.Load(path, LoadOptions.None);

var nodes = doc.Root.Element("links").Elements("link");
foreach (var node in nodes) {
    var pageNameElement = node.Element("pagename");
    XAttribute permAttribute = pageNameElement.Attribute("permission");
    string permission = "";
    if (permAttribute != null)
        permission = permAttribute.Value;
    string text = pageNameElement.Value;
    // Do something with the values...
}

You can of course initialize the XDocument with a stream, if that’s what you already have. Hope this helps 🙂