Proprietary DOM Extensions

Joe Marini makes an interesting point in his book The Document Object Model.

The DOM was also designed to be open and extensible; that is a vendor may add methods and properties outside of those that the DOM specification defines, yet still be considered to be compliant with the DOM spec. Microsoft, for example, provides several Internet Explorer–specific extensions to the DOM API for developers’ convenience without breaking compliance with the base DOM specification.

Although the term “proprietary extensions” give people nightmares, a few of the most useful ones were adopted by other modern browsers due to their usefulness: the innerHTML property and the XMLHttpRequest object. I have no dilemma with these. These extensions circumvented the “standards body” because W3C was too slow to move: too many hands in the pot. This brings upon W3C paralysis by analysis—a deadly decease for a fast–paced industry like ours.

On the other hand, the way events are handled in IE is a deviation. That’s the stuff that gives us nightmares. That’s the stuff that shouldn’t be encouraged or approved.