I wanted to create a nice, simple template for Bootstrap 3.0 that uses a failover technique I learned about at a recent ASP.NET user group meeting (Thanks Alek Davis).
The Getting Started section of http://getbootstrap.com shows a CDN example, but the HTML template that assumes you have local Bootstrap JS and CSS files. I found lots of examples of Javascript failover techniques, most notably Scott Hanselman’s CDNs fail, but your scripts don’t have to… blog post. A little more Googling turned up this technique to see if Bootstrap loaded properly. I adapted the code from github to the shorthand code from Scott’s blog to create this nice Bootstrap 3 HTML template that attempts to load JQuery and the Bootstrap 3 JS and CSS files from CDN. Should any fail, it loads the files locally.
Note: This template is expecting the following local resources:
js/jquery-1.11.0.min.js
js/bootstrap.min.js
css/bootstrap.min.css
May not be IE compatible!
May not be IE compatible!
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Bootstrap 101 Template</title>
<!-- Latest compiled and minified Bootstrap 3 CSS CDN-->
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css">
</head>
<body>
<h1>Hello, world!</h1>
<!-- jQuery (necessary for Bootstrap's JavaScript plugins) CDN Failover -->
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<script>window.jQuery || document.write('<script src="js/jquery-1.11.0.min.js">\x3C/script>');</script>
<!-- Include all compiled plugins (below), or include individual files as needed -->
<!-- Latest compiled and minified JavaScript CDN Failover-->
<script src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
<script>$.fn.modal || document.write('<script src="js/bootstrap.min.js">\x3C/script>');</script>
<script>
$(document).ready(function() {
//CSS CDN Failover (If you change the body color, you will need to change the rgb value below.)
$('body').css("color") == 'rgb(51, 51, 51)' || $("head").prepend("<link rel='stylesheet' href='css/bootstrap.min.css' type='text/css' media='screen'>");
});
</script>
</body>
</html>
References:
Scott Hanselman: CDNs fail, but your scripts don't have to - fallback from CDN to local jQuery
GitHub MaxCDN / bootstrap-cdn: Check if Bootstrap is loaded #111
Bootstrap Website: http://getbootstrap.com
