Darryl Lyons’ Blog

Ever thought about using Microsoft’s HTML Application (HTA) technology? If you are developing AJAX applications for internal customers and have standardized on Internet Explorer, then I would highly recommend this route.

Basically, a HTA only uses the Internet Explorer rendering engine, so you don’t get any of the browser add-ons such as the toolbar, status bar, and address bar. The back button is not available. You get a blank canvas on which to work.

The other benefits include:

• Complete access to local machine
• Smaller memory footprint
• A bit quicker than using the browser
• No back button
• No context menu

Disadvantages:

• Only runs on Windows machines
• Uses IE rendering engine
• User is prompted to RUN the application (because of security)

One of the less obvious benefits is that a HTA pretty much eliminates some of the closure memory leak problems with IE. Basically, whenever you destroy DOM elements (and leave/refresh a page), expando properties that reference JavaScript objects are not cleaned up. This in turn means that memory allocated to the DOM element is not freed.

When you close a HTA (there is no concept of refreshing the page other than F5), you destroy the entire process – hence the memory leaks are not an issue. If you create and destroy DOM elements within the application however, then you will still have to handle these appropriately.

Anyone else play with HTAs?