title: How do I update text inside CDATA
body: <p>I want to replace text inside cdata section but when I simply trying to add text to it I lose CDATA definition.</p>
  
  <p>I have a XML like this:</p>
  
  <pre><code>&lt;title&gt;&lt;![CDATA[string]]&gt;&lt;/title&gt;
  </code></pre>
  
  <p>When I try to update this field with new value:</p>
  
  <pre><code>myXmlNode.SelectSingleNode("title").InnerText = TextBoxName.Text;
  </code></pre>
  
  <p>Output is </p>
  
  <pre><code>&lt;title&gt;string&lt;/title&gt;    
  </code></pre>
  
  <p>How do can I keep it as CDATA?</p>