PNG Transparency for Internet Explorer

Ever wanted to allow your users to see transparent PNG images using Internet Explorer? Now you can!

[high]Note:[/high] I did NOT create this script, it remains the sole property of it's author.


Pros & Cons

Pros:

• Ignored as a comment in other browsers, so no browser-sniffing code is required
• Works with (X)HTML Strict & Transitional Doctypes
• Does not break W3C validation
• Lightweight and very easily deployed
• Works with existing in-line or external CSS rules based on class or ID selectors
• Works with old-style img align="left" or align="right" attributes
• Adds itself to the end of any existing Body Onload code
• Works with imagemaps and input images using a special version

Cons:

• Doesn't work in IE versions earlier than 5.5
• Requires JavaScript to be enabled - the estimations for how many people choose not to use JS vary wildly.
• CSS backround PNGs not supported - experimentation revealed I could traverse the Stylesheets collection and use the AlphaImageLoader trick to replace all background-image attributes containing PNGs, but then background-repeat would not work, and anchors placed over non-transparent parts of the image were not clickable :-(
• CSS rules for the PNG images based on the img selector are lost, but this is easily rectified by adding a class selector to your img rule such that img{..} becomes img,.png{..} - then add the attribute class="png" to each of your PNGs.

To install, simply upload the attached .js file to your /forums/clientscript/ directory.

Then edit your headinclude template, and add the following:

<!--[if lt IE 7.]>
<script defer type="text/javascript" src="clientscript/vbulletin_pngfix.js?v=$vboptions[simpleversion]"></script>
<![endif]-->

You're all set.!
Note: Updated to reflect changes by the author, and 3.5.x javascript handling changes. This template modification works fine with 3.6.x as it is, and therefore won't be posted in the 3.6.x forum!

[rolandogomez]

Works great in VB 3.8 RC, http://www.phototherapy.org. Thanks!

[y2krazy]

Installed. Working like a charm!

vB Version: 3.8.1
IE Version: 6.0.2900.2180

Thank you VERY much!!

~ Sean

[Phobos49]

Thanks!!!! Perfect!!!

vB Version: 3.8.2
IE Version: 6.0.2900.5512

[Pandadisossato]

I can confirm that it work properly with:

vb Version: 3.8.4

Thanks