title: IE9 "Invalid calling object" when printing PDF in iframe
body: <p>I'm opening an editable form PDF (opened via the acrobat plugin) in an iframe:</p>
  
  <pre><code>&lt;iframe name="iframe_content" id="iframe_content" src="mypdf.pdf"&gt;&lt;/iframe&gt;
  </code></pre>
  
  <p>There is a button that calls the following print function:</p>
  
  <pre><code>function printContent(){
      window.frames["iframe_content"].focus();
      window.frames["iframe_content"].print();
  }
  </code></pre>
  
  <p>It works in Chrome, Safari, IE8, but not in IE9.<br>
  In IE9 i receive the following error in reference to the <code>printContent()</code> function:</p>
  
  <pre><code>Invalid calling object 
  </code></pre>
  
  <p>I think this may be the trick to getting it to work, but I'm not sure how to make <code>window.frames</code> fit within this structure: <a href="http://msdn.microsoft.com/en-us/library/ie/gg622930%28v=vs.85%29.aspx" rel="noreferrer">http://msdn.microsoft.com/en-us/library/ie/gg622930%28v=vs.85%29.aspx</a> </p>
  
  <p><strong>UPDATE</strong>: Decided that for this single page the simplest solution was forcing the browser into IE8 compatibility mode using the <code>&lt;meta&gt;</code> tag and <code>X-UA-Compatible</code></p>