XML Hacks

Grouping in XSLT 1.0 and 2.0

If your nodes are out of sorts in your source, use grouping to bring them into line.

This hack shows you several techniques for grouping nodes in the output of an XSLT processor. The first uses XSLT 1.0 and the Muenchian method, named after Steve Muench (see http://www.oreillynet.com/pub/au/609). The second uses XSLT 2.0, which is simpler than the XSLT 1.0 method.

Grouping with XSLT 1.0

The problem that grouping solves is that nodes may not be grouped to your liking in the source document. For example, look at group.xml (Example 3-54).

Example 3-54. group.xml

<?xml version="1.0" encoding="US-ASCII"?> <?xml-stylesheet href="group.xsl" type="text/xsl"?> <uscities> <western> <uscity state="Nevada">Las Vegas</uscity> <uscity state="Arizona">Phoenix</uscity> <uscity state="California">San Francisco</uscity> <uscity state="Nevada">Silver City</uscity> <uscity state="Washington">Seattle</uscity> <uscity state="Montana">Missoula</uscity> <uscity state="Washington">Spokane</uscity> <uscity state="California">Los Angeles</uscity> <uscity state="Utah">Salt Lake City</uscity> <uscity state="California">Sacramento</uscity> <uscity state="Idaho">Boise</uscity> <uscity state="Montana">Butte</uscity> <uscity state="Washington">Tacoma</uscity> <uscity state="Montana">Helena</uscity> <uscity state="Oregon">Portland</uscity> <uscity state="Nevada">Reno</uscity> <uscity state="Oregon">Salem</uscity> <uscity state="Oregon">Eugene</uscity> <uscity state="Utah">Provo</uscity> ...