March 12, 2002 - Using Root Context to Search for DOMDocument Nodes | WebReference

March 12, 2002 - Using Root Context to Search for DOMDocument Nodes

Yehuda Shiran March 12, 2002
Using Root Context to Search for DOMDocument Nodes
Tips: March 2002

Yehuda Shiran, Ph.D.
Doc JavaScript

The "/" pattern in DOMDocument node searching denotes the same rule as in the Unix operating system: "system root." For example, the /sales pattern matches the top level sales node (try it):

  var matchedNodes = xmlDoc.selectNodes('/sales');
  alert("Number of matched nodes: " + matchedNodes.length);
Notice that the forward slash denotes the root of the DOMDocument tree, as in Unix. Trying for the pattern /week won't match any node because there are no week nodes at the root of the tree (try it):

  var matchedNodes = xmlDoc.selectNodes('/week');
  alert("Number of matched nodes: " + matchedNodes.length);
Here is mydvd7.xml for your reference:

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="mydvd7.xsl"?>
<!DOCTYPE sales SYSTEM "mydvd7.dtd">
  <sales>
    <summary>
      <heading>MyDVD Rental Store</heading>
      <subhead>Periodical Sales Report</subhead>
      <description>Sales Report for January, February, 
	    and &lt;&month;&gt; of 2001</description>
      <author>author: &preparedby;</author>
      <date>Jan 30, 2002</date>
    </summary>
    <data>
      <month>
        <name>January 2001</name>
        <week number="1" dvds_rented="12000" />
        <week number="2" dvds_rented="15000" />
        <week number="3" dvds_rented="18000" />
        <week number="4" dvds_rented="11800" />		  
      </month>
      <month>
        <name>February 2001</name>
        <week number="1" dvds_rented="11500" />
        <week number="2" dvds_rented="12390" />
        <week number="3" dvds_rented="19050" />
        <week number="4" dvds_rented="11200" />		  
      </month>
      <month>
        <name>March 2001</name>
        <week number="1" dvds_rented="15300" />
        <week number="2" dvds_rented="12390" />
        <week number="3" dvds_rented="10050" />
        <week number="4" dvds_rented="11230" />		  
      </month>
    </data>
  </sales>