While that XPath query certainly works with the example XML the OP gave, it should be noted it will stop working or give possibly unintended results in any of the following three cases, while the solution with registerNs will continue working correctly (being namespace-aware).

  1. The namespace prefix of the login element changes (and setNamespace isn't used)
  2. A namespace prefix is added on any of the nodes named in the XPath expression that currently don't have one
  3. Any elements are added to the document which happen to have the same prefix+name, regardless of their actual namespace (the expression will match those too)

In reply to Re^2: Xpath not working by Anonymous Monk
in thread Xpath not working by njack

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