使用Google CDN jQuery，但回退到本地副本

Posted 2021-02-22

Grab Google CDN's jQuery. Fall back to local if necessary, Taken from the html5 Boilerplate.

<!-- Grab Google CDN's jQuery. fall back to local if necessary -->
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script>!window.jQuery && document.write('<script src="js/jquery-1.4.2.min.js"></script>')</script>