title: ReCaptcha 2.0: enable Submit button on callback if recaptcha successful
body: <p>I have a very simple form as follows. I want to make it so that the Submit button is disabled, and only enabled <strong>after</strong> the user has successfully completed the ReCaptcha.</p>
  
  <p>I'm assuming I'm going to need some Javascript / jQuery to do this.</p>
  
  <p>Google's documentation on ReCaptcha 2.0 seems really sparse and dense (to me, anyway). I'd appreciate some pointers:</p>
  
  <pre><code>&lt;form action="something.php" method="post"&gt;
      Name: &lt;input type="text" size="40" name="name"&gt;&lt;br&gt;&lt;br&gt;
      &lt;div class="g-recaptcha" data-sitekey="############-#####"&gt;&lt;/div&gt;
      &lt;input type="submit" value="Submit" &gt;
  &lt;/form&gt;
  </code></pre>