Is it bad practice to add non standard attributes to DOM elements? - HTML/Javascript [duplicate]

Answer 1

HTML5 supports "data" type attributes, but in general for a modern day site, this would cause most sites to fail validation if they are going for any doctype other than HTML5.

So that would just be adding a barrier to entry for potential users of your library.

Answer 2

Don't do it. I've learned the hard way that this is not cross-browser. I had a jQuery-intensive app totally fail to function in Chrome because of this.

Answer 3

Without knowing exactly what you're trying to achieve it's difficult to advise whether adopting this kind of approach is the best way or not. However, it's worth pointing out that there are other libraries out there that are successfully using the HTML5 data- attributes referred to by jondavidjon. For an example of this, check out KnockoutJS - fully cross-browser compatible (including IE6).