title: Extract html nodes having not specific child or tags by HTML Agility?
body: <p>I am using HTML Agility Pack and I have a scnerio where I have to fetch collection of some html nodes from a html document having not <strong>button</strong> tags. Apart from this, I need complete collection of html elements. For Example my html document might be like this</p>
  
  <pre><code>&lt;p&gt; This is first free text &lt;/p&gt;
  
  &lt;p&gt; &lt;button class='testButton'&gt; this is first button &lt;/button&gt; &lt;/p&gt;
  
  &lt;strong&gt; &lt;p&gt; This is second free text &lt;/p&gt; &lt;/strong&gt; 
  
  &lt;button class='testButton'&gt; this is second button &lt;/button&gt; 
  </code></pre>
  
  <p>Now I need html node collection of first and second free text tags. Currenly I am able to fetch all button nodes/tags collection from the document by using xpath </p>
  
  <pre><code> html.DocumentNode.SelectNodes(@"//button[starts-with(@id, 'btn~~')]");
  </code></pre>
  
  <p>Now I need collection of all nodes having other <strong>than button tags</strong> also. Kindly guide</p>