I am looking at the custom attributes feature of html 5 here at this link http://ejohn.org/blog/html-5-data-attributes/
This look like the perfect thing for when I am using jquery/javascript.
My question, Is HTML 5 supported by all the main browsers?
example
<li class="user" data-name="John Resig" data-city="Boston"
data-lang="js" data-food="Bacon">
<b>John says:</b> <span>Hello, how are you?</span>
</li>
no, not yet. wait at least until gecko and webkit support it.
ps: you could use html 5 with data attributes anyway, if you need it for javascript purposes. or choose some other unused attributes (title, abbr, ...others?)
As of August 25, HTML 5 is still a working draft. http://dev.w3.org/html5/spec/Overview.html
Parts of HTML 5 are supported by the Safari, Firefox and Opera, but they are not necessarily incorporating the same parts.
It seems that Firefox is the most ahead, from my experience, but it will be years before the majority of browsers users use will support it.
So, until then we will need to continue trying to use it when we can, in browsers that support the new features, and having workarounds for users that haven't updated yet, or continue to use IE.
HTML5 isn't even closed to completly support on any browser yet, and some browsers (Notable the IE's) have no intentions on supporting it at this time.
No.
The Wikipedia page "Comparison of layout engines (HTML 5)" does a good job of listing which engines have implemented which parts of HTML5.
There is currently a lot of red boxes on those tables, and that is based on the latest development version, not the version most users will be using.
Full support of HTML 5 is a way off BUT...
Creating custom attributes is nothing new and is likely to work in all the main browsers - but test to be sure that it will work in your case.
We can use HTML 5 now, just not all of it. A lot of HTML 5 is about formalising the way that HTML is currently used and ensuring backwards compatibility - so if a feature works in browsers now, use it.
Various portions of HTML5 are supported by the different browsers, for various definitions of 'supported'.
Several parts work right now, reliably. The data-* attributes you ask about in your question work just fine in every browser, even IE6; however, nobody yet supports the fun "dataset" method to access them. As long as you're fine with just grabbing them by the full attr name, you're golden. I use them to store state all the time in my webapps, as they're the officially blessed method for doing so.
Wikipedia has a good summary of the various support levels across browsers: http://en.wikipedia.org/wiki/Comparison_of_layout_engines_(HTML_5)
Almost no web technology is completely supported by any browser; no bugs, quirks or issues.
HTML5 is designed for backwards compatibility, and it will hardly break your site (take <input type=url> for instance - non-supporting browsers show an ordinary text box, Opera lets you select an URL from history/bookmarks). I'd go by the approach: develop, try in the browsers you need to support - if it works, awesome. If not, don't use it. Just like with other specs.