PHP: Set the SAX handlers to be called when the XML document gets processed

Description

void xslt_set_sax_handlers ( resource $processor , array $handlers )

xslt_set_sax_handlers() registers the SAX handlers for the document, given a XSLT processor resource.

Using xslt_set_sax_handlers() doesn't look very different than running a SAX parser like xml_parse() on the result of an xslt_process() transformation.

Parameters

processor

The XSLT processor link identifier, created with xslt_create().

handlers

handlers should be an array in the following format:


<?php



$handlers = array(



  "document" => array(

    "start_doc",

    "end_doc"),



  "element"  => array(

    "start_element",

    "end_element"),



  "namespace" => array(

    "start_namespace",

    "end_namespace"),



  "comment"   => "comment",



  "pi"        => "pi",



  "character" => "characters"



);

?>

Where the functions follow the syntax described for the scheme handler functions.

Note: The given array does not need to contain all of the different sax handler elements (although it can), but it only needs to conform to "handler" => "function" format described above.

Each of the individual SAX handler functions are in the format below:

start_doc ( resource $processor )
end_doc ( resource $processor )
start_element ( resource $processor , string $name , array $attributes )
end_element ( resource $processor , string $name )
start_namespace ( resource $processor , string $prefix , string $uri )
end_namespace ( resource $processor , string $prefix )
comment ( resource $processor , string $contents )
pi ( resource $processor , string $target , string $contents )
characters ( resource $processor , string $contents )

Return Values

No value is returned.

Examples

Example #1 xslt_set_sax_handlers() Example


<?php

// From ohlesbeauxjours at yahoo dot fr

// Here's a simple example that applies strtoupper() on

// the content of every <auteur> tag and then displays the

// resulting XML tree:



$xml='<?xml version="1.0"?>

<books>

 <book>

  <title>Mme Bovary</title>

  <author>Gustave Flaubert</author>

 </book>

 <book>

  <title>Mrs Dalloway</title>

  <author>Virginia Woolf</author>

 </book>

</books>';



$xsl='<?xml version="1.0"?>

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:output method="html" encoding="ISO-8859-1" indent="no" omit-xml-declaration="yes"/>

<xsl:template match="/">

 <xsl:for-each select="books/book">

  <livre>

   <auteur><xsl:value-of select="author/text()"/></auteur>

  </livre>

 </xsl:for-each>

</xsl:template>

</xsl:stylesheet>';



// Handlers :

function start_document()

{

  // start reading the document

}



function end_document()

{

  // end reading the document

}



function start_element($parser, $name, $attributes)

{

  global $result,$tag;

  $result .= "<". $name . ">";

  $tag = $name;

}



function end_element($parser, $name)

{

  global $result;

  $result .= "</" . $name . ">";

}



function characters($parser, $data)

{

  global $result,$tag;

  if ($tag == "auteur" ) {

    $data = strtoupper($data);

  }

  $result .= $data;

}



// Transformation :

$xh = xslt_create();

$handlers = array("document" => array("start_document","end_document"),

   "element" => array("start_element","end_element"),

   "character" => "characters");



xslt_set_sax_handlers($xh, $handlers);

xslt_process($xh, 'arg:/_xml', 'arg:/_xsl', NULL, array("/_xml"=>$xml, "/_xsl"=>$xsl));

xslt_free($xh);

?>

You can also use xslt_set_object() if you want to implement your handlers in an object.

Example #2 Object oriented handler


<?php

// This is the object oriented version of the previous example

class data_sax_handler {



  var $buffer, $tag, $attrs;



  var $_xh;



  function data_sax_handler($xml, $xsl)

  {

      // our xslt resource

      $this->_xh = xslt_create();



      xslt_set_object($this->_xs, $this);



      // configure sax handlers

      $handlers = array(

        "document" => array('start_document', 'end_document'),

        "element" => array('start_element', 'end_element'),

        "character" => 'characters'

      );



      xslt_set_sax_handlers($this->_xh, $handlers);



      xslt_process($this->_xh, 'arg:/_xml', 'arg:/_xsl', NULL, array("/_xml"=>$xml, "/_xsl"=>$xsl));

      xslt_free($this->_xh);





  }



  function start_document()

  {

        // start reading the document

  }



  function end_document() {

        // complete reading the document

  }



  function start_element($parser, $name, $attributes) {

        $this->tag = $name;

        $this->buffer .= "<" . $name . ">";

        $this->attrs = $attributes;

  }



  function end_element($parser, $name)

  {

        $this->tag = '';

        $this->buffer .= "</" . $name . ">";

  }



  function characters($parser, $data)

  {

    if ($this->tag == 'auteur') {

          $data = strtoupper($data);

    }

    $this->buffer .= $data;

  }



  function get_buffer() {

    return $this->buffer;

  }



}



$exec = new data_sax_handler($xml, $xsl);



?>

Both examples will output:

<livre>
   <auteur>GUSTAVE FLAUBERT</auteur>
</livre>
<livre>
   <auteur>VIRGINIA WOOLF</auteur>
</livre>