title: Form Button Disable Not Working On Submit
body: <p>I am trying to disable my button after a submit request is sent. I tried the example below, but it is not working as expected.</p>
  
  <p>Why isn't this code working as expected?</p>
  
  <pre class="lang-js prettyprint-override"><code>$(document).ready(function() {
    $('#userSignUp').submit(function() {
      $("input[type='submit']", this).val("Please Wait...").attr('disabled', 'disabled');
      return true;
    });
  });
  </code></pre>
  
  <pre class="lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"&gt;&lt;/script&gt;
  &lt;form action="/sign-up" method="post" id="userSignUp"&gt;
    ...
    &lt;button type="submit" class="login-sign-up-button"&gt;Submit&lt;/button&gt;
  &lt;/form&gt;
  </code></pre>