XPath to select multiple tags

Question

given this simplified data format:

<a>
    <b>
        <c>C1</c>
        <d>D1</d>
        <e>E1</e>
        <f>don't select this one</f>
    </b>
    <b>
        <c>C2</c>
        <d>D2</d>
        <e>E1</e>
        <g>don't select me</g>
    </b>
    <c>not this one</c>
    <d>nor this one</d>
    <e>definitely not this one</e>
</a>

How would you select all the Cs, Ds and Es that are children of B elements?

Basically, something like:

a/b/(c|d|e)

In my own situation, instead of just "a/b/", the query leading up to selecting those C,D,E nodes is actually quite complex so I'd like to avoid doing this:

a/b/c|a/b/d|a/b/e

...if that's possible?

Answer 1

You can avoid the repetition with an attribute test instead:

a/b/*[local-name()='c' or local-name()='d' or local-name()='e']

Contrary to Dimitre's antagonistic opinion, the above is not incorrect in a vacuum where the OP has not specified the interaction with namespaces. The self:: axis is namespace restrictive, local-name() is not. If the OP's intention is to capture c|d|e regardless of namespace (which I'd suggest is even a likely scenario given the OR nature of the problem) then it is "another answer that still has some positive votes" which is incorrect.

You can't be definitive without definition, though I'm quite happy to delete my answer as genuinely incorrect if the OP clarifies his question such that I am incorrect.

Answer 2

Not sure if this helps, but with XSL, I'd do something like:

<xsl:for-each select="a/b">
    <xsl:value-of select="c"/>
    <xsl:value-of select="d"/>
    <xsl:value-of select="e"/>
</xsl:for-each>

and won't this XPath select all children of B nodes:

a/b/*

Answer 3

One correct answer is:

     /a/b/*[self::c or self::d or self::e]

Do note that another answer that still has some positive votes, its author initially removed it but later put it back again:

a/b/*[local-name()='c' or local-name()='d' or local-name()='e']

is both too-long and incorrect. This XPath expression will select nodes like:

• OhMy:c

• NotWanted:d

• QuiteDifferent:e