Conditionals is a new stack which allows you to hide or display stacks, dependant on the ruleset you devise. It can be used to display informational messages in older versions of IE (Internet Explorer), to warn of impending compatibility issues. It can also be used to hide certain stacks in older versions of IE or provide links or page content which is more accessible. The Conditionals stack can be used to either hide or display content, based on the version of IE detected. You can also control if that content is hidden or shown in other web browsers which do not meet the ruleset you create.

Case example #1

You just got that awesome new stack from your favourite developer. But unknown to you, the stack does not work in IE7 and the developer does not wish to support IE7 any more. This presents the unfortunate problem of any IE7 users seeing a rather broken page. Simply drop your new stack inside the Conditionals stack, set the detection criteria to is equal to or less than, set the browser version to IE7, and select the Hidden action. Now the problematic stack will be hidden from view, when IE5, IE6 or IE7 visits the page.

Case example #2

You successfully managed to hide the broken stack in some older versions of IE. But you still want blocked IE users to access the content in an alternative format. So at this point you add a second Conditionals stack to the page. This time you set the criteria the same as before, but you set the Conditionals stack to Display in older versions of IE, and Hidden in other web browsers. Now you have a container that will only display in older versions of IE, and your alternative content can go in there instead.

The Conditionals stack works by reading the user-agent information a web browser visiting your page presents, and imposes the ruleset you devise in the conditional settings. It works most of the time, but if a user has hacked their user-agent settings and modified them to something else, it can give false results.

It would be easy enough to take a hard-line approach and just ignore the problems older versions of IE present. Market share of these browsers continues to fall, and the simple fix is for people to update their browser and use something better! However that is not an option for many people, and some clients you may be working on behalf of will still stipulate support for older web browsers in their design proposals. I've looked at a couple of proposals recently, and IE7 has been marked as the minimum baseline for compatibility, with IE6 listed in a couple as well.

Conditionals is slightly similar to the excellent Browser Reject stack by Joe Workman, in that it can detect legacy versions of IE and display messages urging people to update. I'd still certainly recommend you try and sneak Joe's stack somewhere into your website, because it is a mighty useful stack. However Conditionals differs from the Browser Reject stack, in that it lets you individually hide or show stacks, and will present a modified version of the page for users of older IE versions you opt to target.

I was recently asked who the worst culprits are for still using antiquated versions of IE. That is a tough one to call, although it would seem most of the market share is held by financial institutions (e.g. banks, brokers and accountants), and quite a number of government departments and health services are using some dusty-old setups. Presumably cost is a factor in not updating their software, but I suspect other factors like the use of Visual Basic plugins and other software that only works with certain versions of IE. Most 'home' users have probably updated their computers within the last 5 years, and are probably (hopefully) running newer versions of browsers. Undoubtedly top-100 websites like AOL, Facebook, Google and Twitter have forcefully helped get browsers updated, by dropping support for older versions of IE.

More information about the new Conditionals stack can be found on this page:
http://www.stacks4stacks.com/conditionals/
My thanks to Steve Murphy for proposing this stack idea to me. Steve has written a nice message here on the forums about the Conditionals stack.

Feel free to leave any comments below about what browser usage statistics you're seeing on your websites or any other feedback about the Conditionals stack. Browser support is always a contentious issue, so it would be great to read what you're thinking!