title: Add CSS class dynamically in code behind using c#
body: <p>Hi i want to add CSS class dynamically in code behind.</p>
  
  <p>It's easy to add, but I have little different structure.</p>
  
  <p>I have one master page which has one div like this:</p>
  
  <pre><code>&lt;div class="contnav_bg" id="wrapper"&gt;
  
  //  some content
  
  
  &lt;div&gt;
  </code></pre>
  
  <p>I want <code>class="contnav_bg"</code> to be applied only to dashboard.aspx page.</p>
  
  <p>Right now it applies to all pages.</p>
  
  <p>Can I have to create function for it or anything else.</p>
  
  <p>Thanks</p>