title: How to check if Google form was submitted?
body: <p>So, I have a client that wants to use Google Forms for a form on their website. They also want the user to be able to download some resources after successfully submitting the form. The problem is that the Google form has to be embedded with an iframe, so I can't find a way to check if the form has been submitted since it's happening within the iframe. </p>
  
  <p>The mark up would be like this: </p>
  
  <pre><code>&lt;div&gt;
  &lt;iframe  
  src="https://docs.google.com/forms/d/e/1FAIpQLSdtWuGTwEZEoqJAo0TXJt0LIMSO4g0Mot
  YeVFUNY0slXBP4kQ/viewform?embedded=true" id="googleForm" width="760" height="500" frameborder="0" marginheight="0" marginwidth="0"&gt;Loading...
  &lt;/iframe&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>My question is: is there any way at all to check if the form was submitted, via jQuery, plain Javascript or anything else? Or, is there any script, or settings I can use within Google Forms to feed the user custom HTML after submitting the form? </p>