XSL Filtering

XSL Filter Query

Where to put the Filter Information

Take a new look at the XML document that you have seen in almost every chapter (or open it with IE5):

<?xml version="1.0" encoding="ISO8859-1" ?>
<CATALOG>
  <CD>
    <TITLE>Empire Burlesque</TITLE>
    <ARTIST>Bob Dylan</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Columbia</COMPANY>
    <PRICE>10.90</PRICE>
    <YEAR>1985</YEAR>
  </CD>

To filter the XML file, simply add filter to the select attribute in your for-each element like this:

<xsl:for-each select=”CATALOG/CD[ARTIST=’Bob Dylan’]”>

Leagal filter operators are:

= (equal)
=! (not equal)
&LT& less than
&GT& greater than

Now take a look at your slightly adjusted XSL stylesheet (or open it with IE5):

<?xml version='1.0'?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/TR/WD-xsl">
<xsl:template match="/">
  <html>
  <body>
    <table border="2" bgcolor="yellow">
      <tr>
        <th>Title</th>
        <th>Artist</th>
      </tr>
      <xsl:for-each select="CATALOG/CD[ARTIST='Bob Dylan']">
      <tr>
        <td><xsl:value-of select="TITLE"/></td>
        <td><xsl:value-of select="ARTIST"/></td>
      </tr>
      </xsl:for-each>
    </table>
  </body>
  </html>
</xsl:template>
</xsl:stylesheet>

Transforming it on the Client

Here is the simple source code needed transform the XML file to HTML on the client (try it yourself):

<html>
<body>
<script language="javascript">
// Load XML 
var xml = new ActiveXObject("Microsoft.XMLDOM")
xml.async = false
xml.load("cd_catalog.xml")

// Load the XSL
var xsl = new ActiveXObject("Microsoft.XMLDOM")
xsl.async = false
xsl.load("cd_catalog_filter.xsl")

// Transform
document.write(xml.transformNode(xsl))
</script>

</body>
</html>