How to parse an XML File

Question

I have an XML file that looks like:

  <results>
    <result>
      <title>Welcome+to+The+JASON+Project%21</title>
      <url>http%3A%2F%2Fwww.jason.org%2F</url>
      <domain />
      <inside_links>
        <inside_link>
          <description>News</description>
          <url>http%3A%2F%2Fwww.jason.org%2FPublic%2FNews%2FNews.aspx</url>
        </inside_link>
        <inside_link>
          <description>register</description>
          <url>http%3A%2F%2Fwww.jason.org%2Fpublic%2Fregistration%2Fregistration.aspx</url>
        </inside_link>
        <inside_link>
          <description>Argonauts</description>
          <url>http%3A%2F%2Fwww.jason.org%2FPublic%2FArgonauts%2FArgonauts.aspx</url>
        </inside_link>
        <inside_link>
          <description>Curriculum</description>
          <url>http%3A%2F%2Fwww.jason.org%2FPublic%2FCurriculum%2FCurriculum.aspx</url>
        </inside_link>
        <inside_link>
          <description>Credits</description>
          <url>http%3A%2F%2Fwww.jason.org%2Fpublic%2FMisc%2FCredits.aspx</url>
        </inside_link>
      </inside_links>
      <inside_keywords>National+Science+Education+Standards, National+Geographic+Society, Physical+Science, Professional+Development, Earth+Science</inside_keywords>
    </result>
  </results>

...And I'm very confused as to how to read it. I simply want to get the Title, Description, and URL into separate strings. Something like:

foreach line in lines
string title = gettitle;
string description = getdescription;
string url = geturl;

...I've read so many tutorials but all of them seem to not be relative to what i need to do.. Can somebody please help me out with this?

Answer 1

If you are using .NET 3.5, I'd suggest using LINQ to XML...

XDocument doc = XDocument.Load(filename);
XElement insideLinks = doc.Root.Element("result").Element("inside_links");
foreach (XElement insideLink in insideLinks.Elements())
{
    string description = (string)insideLink.Element("description");
    string url = (string)insideLink.Element("url");
}

This also lets you use the built-in "query" syntax so you could do something like this...

XDocument doc = XDocument.Load(filename);
XElement insideLinks = doc.Root.Element("result").Element("inside_links");
var allTitles = from XElement insideLink 
                in insideLinks.Elements("inside_link")
                select (string)insideLink.Element("title");

(edited per comment)

Answer 2

try this:

XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("yourfile.xml");
foreach (XmlNode result in xmlDoc.SelectNodes("/results/result"))
{
    string title = result.SelectSingleNode("title").InnerText;
    string url = result.SelectSingleNode("url").InnerText;
    foreach (XmlNode insideLink in result.SelectNodes("inside_links/inside_link"))
    {
        string description = insideLink.SelectSingleNode("description").InnerText;
    }
}

Answer 3

To extend the LINQ to XML suggestion, you can use a select clause to create objects to represent the parsed links:

XDocument doc = XDocument.Load(filename);
var links = from link in doc.Descendants("inside_link")
            select new
            {
                Description = (string)link.Element("description"),
                Url = HttpUtility.UrlDecode((string)link.Element("url"))
            };

foreach(var l in links)
    Console.WriteLine("<a href=\"{0}\">{1}</a>", l.Url, l.Description);

In this case, links will be a sequence of objects that have an anonymous type with Description and Url properties, with Url decoded. This foreach would show something like this:

<a href="http://www.jason.org/Public/News/News.aspx"&gt;News&lt;/a&gt;
<a href="http://www.jason.org/public/registration/registration.aspx"&gt;register&lt;/a&gt;
...