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Trying to select an element based on the value of one of it's childrens childrens

Thinking the following but not working, appreciate any help, thanks

./book[/author/name = 'John'] or

./book[/author/name text() = 'John']

Want all books where the author name = 'John'

Xml file

<list>
   <book>
      <author>
         <name>John</name>
         <number>4324234</number>
      </author>
      <title>New Book</title>
      <isbn>dsdaassda</isbn>
   </book>
   <book>...</book>
   <book>...</book>
</list>
James Walsh
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1 Answers1

365

Almost there. In your predicate, you want a relative path, so change 

./book[/author/name = 'John']

to either

./book[author/name = 'John']

or

./book[./author/name = 'John']

and you will match your element. Your current predicate goes back to the root of the document to look for an author.

AakashM
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    Without `.` didn't work for me (needed `./author/name`) – MichaelChirico Oct 11 '18 at 06:03
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    Is it possible to use this syntax in a function? Eg, how to implement something such as `./book[contains(author/name, "John")]`? – Just a learner Oct 22 '18 at 11:00
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    @OgrishMan new questions should go in [New Question](https://stackoverflow.com/questions/ask), but before that I'd just try it! Generally you want single quotes `'` rather than double quotes `"` for string literals in xpath, by the way. – AakashM Oct 22 '18 at 12:25