title: Get attribute value from c#/xpath
body: <p>I have an app.config file, and need to get value of an attribute:</p>
  
  <pre><code>&lt;param name="File" value="C:\"/&gt;
  </code></pre>
  
  <p>Liquid XML Studio gives the following xml:</p>
  
  <pre><code>/configuration/log4net/appender/param[1]
  </code></pre>
  
  <p>However, what C# code can use xpath to get a value?</p>