Is it possible to import css stylesheets into a html page using Javascript? If so, how can it be done?
P.S the javascript will be hosted on my site, but I want users to be able to put in the <head> tag of their website, and it should be able to import a css file hosted on my server into the current web page. (both the css file and the javascript file will be hosted on my server).
I guess something like this script would do:
<script type="text/javascript" src="/js/styles.js"></script>
This JS file contains the following statement:
if (!document.getElementById) document.write('<link rel="stylesheet" type="text/css" href="/css/versions4.css">');
The address of the javascript and css would need to be absolute if they are to refer to your site.
Many CSS import techniques are discussed in this "Say no to CSS hacks with branching techniques" article.
But the "Using JavaScript to dynamically add Portlet CSS stylesheets" article mentions also the CreateStyleSheet possibility (proprietary method for IE):
<script type="text/javascript">
//<![CDATA[
if(document.createStyleSheet) {
document.createStyleSheet('http://server/stylesheet.css');
}
else {
var styles = "@import url(' http://server/stylesheet.css ');";
var newSS=document.createElement('link');
newSS.rel='stylesheet';
newSS.href='data:text/css,'+escape(styles);
document.getElementsByTagName("head")[0].appendChild(newSS);
}
//]]>
The YUI library might be what you are looking for. It also supports cross domain loading.
If you use jquery, this plugin does the same thing.
Here's the "oldschool" way of doing it, which hopefully works accross all browsers. In theory you would use setAttribute unfortunately IE6 doesn't support it consistently.
var $ = document; // shortcut
var cssId = 'myCss'; // you could encode the css path itself to generate id..
if (!$.getElementById(cssId))
{
var head = $.getElementsByTagName('head')[0];
var link = $.createElement('link');
link.id = cssId;
link.rel = 'stylesheet';
link.type = 'text/css';
link.href = 'http://website.com/css/stylesheet.css';
link.media = 'all';
head.appendChild(link);
}
This example checks if the CSS was already added so it adds it only once.
Put that code into a javascript file, have the end-user simply include the javascript, and make sure the CSS path is absolute so it is loaded from your servers.