title: Trying to get a single node with Html Agility Pack
body: <p>I'm trying to get a single node after I locate the htmlnode with a specific tag. 
  But what I get back is an error:</p>
  
  <blockquote>
    <p>Object reference not set to an instance of an object.</p>
  </blockquote>
  
  <p>Now here is the code:</p>
  
  <pre><code>HtmlWeb htmlWeb = new HtmlWeb();
  // Creates an HtmlDocument object from an URL
  HtmlAgilityPack.HtmlDocument document = htmlWeb.Load(url);
  // Targets a specific node
  // If there is no node with that Id, someNode will be null
  HtmlNode someNode = document.GetElementbyId("&lt;li name=\"XU\"&gt;");
  var parseString = someNode.SelectSingleNode("//span[@class='lp']");
  </code></pre>
  
  <p>My purpose is to get all the nodes within the XU li tag. I know the name of the classes.</p>
  
  <p>Also just to note that when I'm replacing the last code line with a </p>
  
  <pre><code>var parseString = document.DocumentNode.SelectSingleNode("//span[@class='long-position']");
  </code></pre>
  
  <p>then the tag argument within the SelectSingleNode is working fine.</p>