title: On a button click, open new text box in Ruby on Rails
body: <p>I have a BlogPost resources, where in BlogPost 'show' screen, I want a "new comment" button to be displayed and only on clicking that button I want the new Comment template to be rendered into the same page. I would like to use ajax concept to do this. How do I do this? </p>
  
  <p>NOTE: I have BlogPost and Comment as seperate resources(plural)
  Resources I've defined in my routes looks like this:</p>
  
  <pre><code>map.resources :blog_posts, :has_many =&gt; :comments
  </code></pre>
  
  <p>EDIT: For a better idea, the 'add comment' link just below a question in stackoverflow</p>