How can I select parent elements that contain empty element with XPath?

Question

I have the following xml:

<rootelement>
   <parentelement>
      <mytype>123</mytype>
      <myvalue>abc</myvalue>
   </parentelement>
   <parentelement>
      <mytype></mytype>
      <myvalue>xyz</myvalue>
   </parentelement>
   <parentelement>
      <mytype />
      <myvalue>qwe</myvalue>
   </parentelement>
   <parentelement>
      <myvalue>asdf</myvalue>
   </parentelement>
</rootelement>

I want to use XPath to select:

   <parentelement>
      <mytype></mytype>
      <myvalue>xyz</myvalue>
   </parentelement>
   <parentelement>
      <mytype />
      <myvalue>qwe</myvalue>
   </parentelement>
   <parentelement>
      <myvalue>asdf</myvalue>
   </parentelement>

When I try this in my xslt:

<xsl:template match="/rootelement/parentelement/mytype[not(text())]/.."/>

it fails with:

Unexpected token in pattern, found ".."

When I try this:

<xsl:template match="/rootelement/parentelement/mytype[not(text())]/parent::*"/>

it fails with:

Axis in pattern must be child or attribute

How can I select parent elements that contain empty mytype?

Thanks!

Answer 1

匹配元素并将条件放入谓词中，例如

<xsl:template match="/rootelement/parentelement[mytype[not(node())]]"/>

Answer 2

You say "parent elements that contain empty mytype". So you select parentelement , followed by a condition: it should contain mytype , and mytype should be empty. By "empty", I assume that you mean no text or elements, so node() is preferrable:

/rootelement/parentelement[mytype[not(node())]]