assuming the followin开发者_如何学Cg html (minus the comments and "nbsp;" etc that xQuery wont process as is) why does this following code work
for $first in fn:doc("file:///index.html")//element()[local-name() = "head"]
return <test>{ $first }</test>
and this
for $first in fn:doc("file:///index.html")//head
return
<test>{ $first }</test>
not work?
Because index.html is XHTML and the <head> you are looking for is in the XHTML namespace.
The first query ignores namespaces because you use the local-name() function.
The second query does not, it explicitly asks for a <head> that is in the empty namespace.
You would need
declare namespace x="http://www.w3.org/1999/xhtml"
for $first in fn:doc("file:///index.html")/x:html/x:head
return <test>{ $first }</test>
Note that I avoid using //, since this goes through the entire tree of the document, even though in this case the only possible position of the <head> is known beforehand. Making it explicit speeds up the XPath query a lot.
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