title: Regex replace for the string
body: <p>I am looking for regex repalce command to replace particular strings. Suppose i want text <code>ss</code> to be replaced by <code>&lt;u&gt;ss&lt;/u&gt;</code> in a HTML code. 
  So if my input is    <code>&lt;p style=""&gt;ss&lt;/p&gt;</code> i want to see output <code>&lt;p style=""&gt;&lt;u&gt;ss&lt;/u&gt;&lt;/p&gt;</code></p>
  
  <p>But i don't want word like</p>
  
  <p><code>&lt;b&gt;Issues&lt;/b&gt;</code> to get replaced like <code>&lt;b&gt;I&lt;u&gt;ss&lt;/u&gt;es&lt;/b&gt;</code></p>
  
  <p>So i need to put a check if its a complte word or apart of the word.</p>
  
  <p>I want regex.replace for</p>
  
  <p><code>"&gt;ss&lt;"</code> &amp; <code>&gt;   ss    &lt;</code></p>
  
  <p>Any has better solution for this?</p>