Preventing portions of a webpage from printing

A colleague asked me about my solution for this just the other day, here’s the quick solution.

  1. Add a CSS class attribute to the items.  Assuming they are <div>’s for header and footer, they would look like my example below, but you can add the ‘no-print’ class to anything you don’t want printed.
  2. Add a stylesheet with media=”print” to change the visibility and/or display attributes of that class.
  3. With a little more work, you could add a ‘no-screen’ solution too… this would be advantageous in cases where you may need to mask an account number or SSN.

<link media=”print” href=”print.css” type=”text/css” rel=”stylesheet” />
<div class=”no-print”>This is your header</div>
<div>this is the body</div>
<div class=”no-print”>this is your footer</div>

print.css could then contain:

.no-print { display:none; }


MSIE PNG Alpha Transparency

In usual form, MSIE doesn’t directly implement Alpha-Transparency on PNG images. Typically this feature is used to allow for anti-aliased gradients on images so that they can be used to support a variety of backgrounds.

There are a variety of solutions online for this problem, however I take issue with most, here’s why:

  • .htc files – this is a proprietary Microsoft solution, to add support on most web servers the MIME type must also be added.
  • filter: progid: – this too is utilizing a standard in Microsoft’s own particular way.

While neither of these is perfect, the ‘filter:’ is obviously the best of two evils. Surround it with the “Conditional If” comments (previously documented) and you’re at least safe for most other browsers.

Here’s my example code:

<!–[if gte IE 5.5000]>
<script type=”text/javascript”>
function correctPNG() // correctly handle PNG transparency in Win IE 5.5 or higher.
for(var i=0; i<document.images.length; i++)
var img = document.images[i]
var imgName = img.src.toUpperCase()
if (imgName.substring(imgName.length-3, imgName.length) == “PNG”)
var imgID = ( ? “id='” + + “‘ ” : “”;
var imgClass = (img.className) ? “class='” + img.className + “‘ ” : “”;
var imgTitle = (img.title) ? “title='” + img.title + “‘ ” : “title='” + img.alt + “‘ “;
var imgStyle = “display:inline-block;” +;
if (img.align == “left”) imgStyle = “float:left;” + imgStyle;
if (img.align == “right”) imgStyle = “float:right;” + imgStyle;
if (img.parentElement.href) imgStyle = “cursor:hand;” + imgStyle;
var strNewHTML = “<span ” + imgID + imgClass + imgTitle
+ ” style=\”” + “width:” + img.width + “px;height:” + img.height + “px;” + imgStyle + “;”
+ “filter:progid:DXImageTransform.Microsoft.AlphaImageLoader”
+ “(src=\'” + img.src + “\’, sizingMethod=’scale’);\”></span>”;
img.outerHTML = strNewHTML;
i = i-1;
window.attachEvent(“onload”, correctPNG);


Good luck out there!

Open Source Diffs/Compare Tools

I often find it necessary to compare separate branches of large programming projects in Java/JSP and PHP. Comparing single files manually proves to be very time consuming. I’ve found that software to do the recursive comparisons makes this much easier as it greatly reduces the effort.

Personally, I’m currently fond of WinMerge (on Windows platforms), though I’ve got a lot of peers that swear by Beyond Compare. Regardless their usage is very similar.


Beyond Compare: