title: Get tags around text in HTML document using C#
body: <p>I would like to search an HTML file for a certain string and then extract the tags.  Given:</p>
  
  <p><code>&lt;div_outer&gt;&lt;div_inner&gt;Happy birthday&lt;div&gt;&lt;div&gt;</code></p>
  
  <p>I would like to search the HTML for "Happy birthday" then have a function return some sort of tag structure: this is the innermost tag, this is the tag outside that one, etc.  So, <code>&lt;div_inner&gt;&lt;/div&gt;</code> then <code>&lt;div_outer&gt;&lt;/div&gt;</code>.</p>
  
  <p>Any ideas?  I am thinking HTMLAgilityPack but I haven't been able to figure out how to do it.</p>
  
  <p>Thanks as always, guys.</p>