XSLT Part 4: Looping and Sorting

As described in the April 2003 issue of CPU - Computer Power User magazine. This article builds on the examples described in the March 2003 issue. These examples are found here (http://www.iangraham.org/writing/cpu-articles/mar03/)

Examples

A) Downloadable ZIP File

• There are lots of little examples here -- why not download the whole lot as a ZIP file -- apr03.zip -- and install them on your own machine?

B) The Raw Data

• demo.xml -- The simple example XML data document used in the article -- this contains the raw data that is transformed into HTML. A plain text version is available at demo.txt.
• demo-withPI.xml -- This is basically the same as demo.xml, but with an xml-stylesheet PI at the beginning of the document referencng the transform.xsl style sheet. Note that you will need to edit this document (and change the name of hte stylesheet) to test out the other example stylesheets. Modern browsers (IE 6 / Mozilla 1+/Netscape 7+) are able to take this XML data, apply the transform to it, and display the generated HTML. A plain text version of this document is available at demo-withPI.txt.

C) The XSLT Stylesheets

• transform.xsl -- The original example XSLT that doesn't sort the output items (same as last months). A plain text version is available at transform.txt.
• transform-sort1.xsl -- The first try at sorting using the markup:

  <xsl:for-each select="/data/item" >
    <xsl:sort select="name" />
    <xsl:apply-templates select="." />
  </xsl:for-each>
  

  This almost gets it right, but messes up the first item (because of leading whitespace). A plain text version is available at transform-sort1.txt.
• transform-sort2.xsl -- The second try at alphabetical sorting, using the markup:

  <xsl:for-each select="/data/item" >
    <xsl:sort select="normalize-space(name)" />
    <xsl:apply-templates select="." />
  </xsl:for-each>
  

  This works properly, because the normalize-space() function removes the leading space characters from the values. A plain text version is available at transform-sort2.txt.
• transform-sort3.xsl -- The third try at alphabetical sorting, using the markup:

  <xsl:apply-templates select="/data/item" >
     <xsl:sort select="normalize-space(name)" />
  </xsl:apply-templates>
  

  This almost gets it right, but messes up the first item (because of leading whitespace). A plain text version is available at transform-sort3.txt.
• transform-sort4.xsl -- In this case sorted numerically by year:

  <xsl:for-each select="/data/item" >
    <xsl:sort data-type="number" 
    select="substring(normalize-space(birthday),string-length(normalize-space(birthday))-3,4)" />
    <xsl:apply-templates select="." />
  </xsl:for-each>
  

  This works fine -- but only if each birthday string actually ends with a four-digit year! plain text version is available at transform-sort4.txt.

Tutorials, Books, References, and Tools

• See the Web site from last November's article, and also from last February 2003 (at the bottom of the page!)