2007/6/29, Simon Pieters:
For HTML elements in HTML documents, why is Element.localName uppercased for tag names and lowercased for attribute names?
Because of this: http://www.w3.org/TR/DOM-Level-2-HTML/html.html#ID-5353782642 and this: http://www.w3.org/2000/11/DOM-Level-2-errata#html-2
I wouldn't expect it to, and it makes it harder to write scripts that work for both HTML and XHTML. For example, if you want a script to work in both legacy HTML UAs and HTML5 UAs as well as in XHTML, you may want to do something like if ((elm.tagName == "A" && !elm.namespaceURI) || (elm.localName == "a" && elm.namespaceURI == "http://www.w3.org/1999/xhtml";)) to check that a given element is an HTML "a" element.
Actually, if you wanted such drastic checks, you'd need yet another condition, because HTML5 puts HTML elements in the XHTML namespace: http://www.whatwg.org/specs/web-apps/current-work/multipage/section-terminology.html#html-namespace So I'd just recommend: if (elm.localName.lower() == "a") { ... } or eventually: if (elm.localName.lower() == "a" && (!elm.namespaceURI || elm.namespaceURI == "http://www.w3.org/1999/xhtml";)) { .... } if you're working in documents with other namespaces. -- Thomas Broyer
