title: webshim and checkValidity() in IE8
body: <p>Following from <a href="https://stackoverflow.com/questions/20088694/manually-invoke-html5-form-validation">Manually invoke HTML5 form validation</a>, I've now tried using webshims to provide HTML5-like form validation in older versions of IE.</p>
  
  <p>Whilst the form validation sort of works (the errors are displayed for fields that have required), the function on <code>&lt;form onsubmit="return verify(this);" &gt;</code> is not prevented from being called.  I'm not sure if it's a reasonable expectation for this to occur.</p>
  
  <p>Secondly, and as fall back, I've added a check in the verify() function to only continue if the form is valid.  To this end, I've added the following code to the verify() function().</p>
  
  <pre><code>function verify(theForm) {
      form = theForm;
  
      if (!form.checkValidity()) {
          return false;
      }
  
      /* continue with recaptcha processing */
  }
  </code></pre>
  
  <p>I'm using IE8 in IETester, because I don't have a real version of IE8 to test with.  It's Javascript debugging seems to suggest that checkValidity() doesn't exist on the form.  I think there is a reasonable expectation that checkValidity should exist for the form, since that is the purpose of webshims.</p>
  
  <p>My initialisation code in the html head is </p>
  
  <pre><code>&lt;script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"&gt;&lt;/script&gt;
  &lt;script src="/branding/js-webshim/minified/extras/modernizr-custom.js"&gt;&lt;/script&gt;
  &lt;script src="//cdnjs.cloudflare.com/ajax/libs/modernizr/2.6.2/modernizr.min.js"&gt;&lt;/script&gt;
  &lt;script src="/branding/js-webshim/minified/polyfiller.js"&gt;&lt;/script&gt;
  &lt;script&gt;
      $.webshims.polyfill('forms');
  &lt;/script&gt;
  </code></pre>
  
  <p>Which is pretty close to the documented method of getting it going.  And webshims seems to be operating in part, because the error messages of required fields missing are displaying.</p>
  
  <p>I've added a demo of what is happening at <a href="http://jsfiddle.net/BqW9D/2/" rel="nofollow noreferrer">http://jsfiddle.net/BqW9D/2/</a>, but I can't run jsfiddle in IETester with IE8 or IE9. It's just a mess.</p>