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Revision: 2133
at January 1, 2007 20:17 by jonhenshaw


Initial Code
<attach event="ondocumentready" handler="parseStylesheets" />
<script>
/**
 *	Whatever:hover - V1.42.060206 - hover & active
 *	------------------------------------------------------------
 *	(c) 2005 - Peter Nederlof
 *	Peterned - http://www.xs4all.nl/~peterned/
 *	License  - http://creativecommons.org/licenses/LGPL/2.1/
 *
 *	Whatever:hover is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU Lesser General Public
 *	License as published by the Free Software Foundation; either
 *	version 2.1 of the License, or (at your option) any later version.
 *
 *	Whatever:hover is distributed in the hope that it will be useful,
 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 *	Lesser General Public License for more details.
 *
 *	Credits and thanks to:
 *	Arnoud Berendsen, Martin Reurings, Robert Hanson
 *
 *	howto: body { behavior:url("csshover.htc"); }
 *	------------------------------------------------------------
 */

var csshoverReg = /(^|\s)(([^a]([^ ]+)?)|(a([^#.][^ ]+)+)):(hover|active)/i,
currentSheet, doc = window.document, hoverEvents = [], activators = {
	onhover:{on:'onmouseover', off:'onmouseout'},
	onactive:{on:'onmousedown', off:'onmouseup'}
}

function parseStylesheets() {
	if(!/MSIE (5|6)/.test(navigator.userAgent)) return;
	window.attachEvent('onunload', unhookHoverEvents);
	var sheets = doc.styleSheets, l = sheets.length;
	for(var i=0; i<l; i++) 
		parseStylesheet(sheets[i]);
}
	function parseStylesheet(sheet) {
		if(sheet.imports) {
			try {
				var imports = sheet.imports, l = imports.length;
				for(var i=0; i<l; i++) parseStylesheet(sheet.imports[i]);
			} catch(securityException){}
		}

		try {
			var rules = (currentSheet = sheet).rules, l = rules.length;
			for(var j=0; j<l; j++) parseCSSRule(rules[j]);
		} catch(securityException){}
	}

	function parseCSSRule(rule) {
		var select = rule.selectorText, style = rule.style.cssText;
		if(!csshoverReg.test(select) || !style) return;

		var pseudo = select.replace(/[^:]+:([a-z-]+).*/i, 'on$1');
		var newSelect = select.replace(/(\.([a-z0-9_-]+):[a-z]+)|(:[a-z]+)/gi, '.$2' + pseudo);
		var className = (/\.([a-z0-9_-]*on(hover|active))/i).exec(newSelect)[1];
		var affected = select.replace(/:(hover|active).*$/, '');
		var elements = getElementsBySelect(affected);
		if(elements.length == 0) return;

		currentSheet.addRule(newSelect, style);
		for(var i=0; i<elements.length; i++)
			new HoverElement(elements[i], className, activators[pseudo]);
	}

function HoverElement(node, className, events) {
	if(!node.hovers) node.hovers = {};
	if(node.hovers[className]) return;
	node.hovers[className] = true;
	hookHoverEvent(node, events.on, function() { node.className += ' ' + className; });
	hookHoverEvent(node, events.off, function() { node.className = node.className.replace(new RegExp('\\s+'+className, 'g'),''); });
}
	function hookHoverEvent(node, type, handler) {
		node.attachEvent(type, handler);
		hoverEvents[hoverEvents.length] = { 
			node:node, type:type, handler:handler 
		};
	}

	function unhookHoverEvents() {
		for(var e,i=0; i<hoverEvents.length; i++) {
			e = hoverEvents[i]; 
			e.node.detachEvent(e.type, e.handler);
		}
	}

function getElementsBySelect(rule) {
	var parts, nodes = [doc];
	parts = rule.split(' ');
	for(var i=0; i<parts.length; i++) {
		nodes = getSelectedNodes(parts[i], nodes);
	}	return nodes;
}
	function getSelectedNodes(select, elements) {
		var result, node, nodes = [];
		var identify = (/\#([a-z0-9_-]+)/i).exec(select);
		if(identify) {
			var element = doc.getElementById(identify[1]);
			return element? [element]:nodes;
		}
		
		var classname = (/\.([a-z0-9_-]+)/i).exec(select);
		var tagName = select.replace(/(\.|\#|\:)[a-z0-9_-]+/i, '');
		var classReg = classname? new RegExp('\\b' + classname[1] + '\\b'):false;
		for(var i=0; i<elements.length; i++) {
			result = tagName? elements[i].all.tags(tagName):elements[i].all; 
			for(var j=0; j<result.length; j++) {
				node = result[j];
				if(classReg && !classReg.test(node.className)) continue;
				nodes[nodes.length] = node;
			}
		}	
		
		return nodes;
	}
</script>

Initial URL
http://www.xs4all.nl/~peterned/csshover.html

Initial Description
IE6 and before doesn't support :hover in CSS (except for anchors). You can use this script to make hovers work in IE. Just add the following line to your stylesheet (this assumes the path of the file -- you may need to change it to reflect your paths).

body { behavior:url(&quot;csshover.htc&quot;); }

Initial Title
Internet Explorer (IE6) CSS Hover

Initial Tags
css, javascript, ie, ie6

Initial Language
CSS