XSLT

How Do I List All the Elements in an XML Document?

As in our last example, this job is for generic XPath expressions. We’ll use the grouping techniques described in Section 6.2 in Chapter 6, along with the name() function, to accomplish this. Our stylesheet sorts all element names alphabetically, and then groups them to list each unique element once, along with a count of how many times that element appears:

<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output method="text"/>

  <xsl:variable name="newline">
<xsl:text>
</xsl:text>
  </xsl:variable>

  <xsl:key name="elements" match="*" use="name()"/>

  <xsl:template match="/">
    <xsl:value-of select="$newline"/>
    <xsl:text>Summary of Elements</xsl:text>
    <xsl:value-of select="$newline"/>
    <xsl:value-of select="$newline"/>
    <xsl:for-each 
      select="//*[generate-id(.)=generate-id(key('elements',name())[1])]">
      <xsl:sort select="name()"/>
      <xsl:for-each select="key('elements', name())">
        <xsl:if test="position()=1">
          <xsl:text>Element </xsl:text>
          <xsl:value-of select="name()"/>
          <xsl:text> occurs </xsl:text>
          <xsl:value-of select="count(//*[name()=name(current())])"/>
          <xsl:text> times.</xsl:text>
          <xsl:value-of select="$newline"/>
        </xsl:if>
      </xsl:for-each>
    </xsl:for-each>
    <xsl:value-of select="$newline"/>
    <xsl:text>There are </xsl:text>
    <xsl:value-of select="count(//*)"/>
    <xsl:text> elements in all.</xsl:text>
  </xsl:template>
    
</xsl:stylesheet>

When we run this stylesheet against the XML source file ...