fixIE8Alpha.js

/**
 *
 */
function doIEHack() {
	var $fixNodes = $('.pngfix');

	// appy filter for all image elements with a 'pngfix' class being attached
	$fixNodes.filter('img').each(function() {
		applyFilterOnNode($(this));
	});

	// appy filter for all background images whose element have a 'pngfix' class (image element excluded)
	$fixNodes.not('img').each(function(i, el) {
		applyFilterOnBackgroundImage($(this));
	});
}

/**
 *
 */
function applyFilterOnBackgroundImage($node) {
	var regex = /url\(["']*(.*?)["']*\)/;
	var src = $node.css("background-image").replace(regex, "$1");
	if (src !== 'none') {
		console.log("fix background " + src);
		$node.css({
			backgroundImage: "none",
			filter: 'progid:DXImageTransform.Microsoft.AlphaImageLoader(src="' + src + '", sizingMethod="scale")'
		});
	} else {
		console.log("backgroundImage is none!");
	}
}

/**
 *
 */
function applyFilterOnNode($node) {
	var src = $node.attr('src');
	if (src.indexOf('.png') !== -1) {
		console.log("fix node " + src);
		$node.css({
			filter: 'progid:DXImageTransform.Microsoft.AlphaImageLoader(src="' + src + '", sizingMethod="scale")'
		});
	}
}

/**
 *
 */
function isIEHackRequired() {
	return (typeof window.addEventListener === 'undefined' && typeof document.getElementsByClassName === 'undefined');
}

if (isIEHackRequired()) {
    doIEHack();
}