title: jQuery: Check if content is sitting inside an iframe
body: <p>I'm loading a page through an iframe. If the content is sitting inside an iframe I need to add a loading spinner and if not, then no need for the spinner.</p>
  
  <p>Problem: 
  How can I use jQuery to check from <strong>within</strong> the content in the iframe if it's currently sitting in an iframe or not?</p>
  
  <p>(i.e. it's simple to add jQuery to the page which loads the iframe itself, but I need the jQuery code to be in the file that's loaded <strong>inside</strong> the iframe).</p>