Question

This is probably something extremely simple but I can’t get my head around it so help would be appreciated 🙂

I have a simple XML file that I’d like to parse and I have a problem accessing element’s values.

This is the XML document I have:

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<application>
    <description>
        <![CDATA[ This is the description of the application. ]]>
    </description>    
    <parameters>
        <param type="int32" name="testvar1" required="false">10</param>
        <param type="string" name="testvar2" required="true" />
        <param type="float" name="testvar3">42.00</param>
    </parameters>
</application>

I load the document from a textbox, like:

var doc = XDocument.Parse(textBox1.Text);

And I use a simple Linq query to filter out stuff:

var parameters = from param in doc.Descendants("param")
                 select new
                 {
                     name = (String)param.Attribute("name"),
                     type = (String)param.Attribute("type"),
                     value = (String)param.Value, // Wrong?
                 };

var data = String.Empty;
foreach (var p in parameters)
{
    data += p.name;
    data += " -- ";
    data += p.type;
    data += " -- ";
    data += p.value;
    data += "\n\r";
}

The output looks like:

testvar1 -- int32 -- 
testvar2 -- string -- 
testvar3 -- float -- 

In other words, the line value = (String)param.Value doesn’t seem to have the desired effect.

EDIT: It seems like I wasn’t reading the correct XML file, my bad. The question below is still valid though…

Also, the following lines causes a NullReferenceException:

var description = (String) doc.Element("description").Value;

So it looks like I don’t quite understand how to get the value of XML elements 🙂 Could you help me fix these?

Thanks.

Answer 1

I was having problems with:

var description = doc.Element("application").Element("description").Value;

or

var description = doc.Element("description").Value;

but this one seems to work:

var description = doc.Descendants("description").First().Value;