xml_set_element_handler - PHP code example

PHP Function XML_Set_Element_Handler

The php function xml_set_element_handler allows you to control how a document is parsed and formatted on an event basis. For example, it lets you set a callback function to be called when the parser encounters the beginning of an element tag, or when it finds the end of one. The handler functions you provide can manipulate the data in any way that you want.

When you first create an XML parser, you can also specify a source encoding for the document to be processed. The supported encodings are ISO-8859-1, US-ASCII and UTF-8. If a document is supplied in an encoding that is not specified, the XML parser will fall back to ISO-8859-1.

In XML documents, attribute names and values are case-folded by default. This is a convenience feature to allow you to access an XML document's attributes in a more readable manner. If you use a callback function for each start and end element tag, then you may need to know the original case of the attribute to use it properly in your application.

The xml_set_element_handler() and xml_set_character_data_handler() functions take the following parameters: a reference to the XML parser created in the call to xml_parser_create, a function prototype for the start element handler (to be called when an XML opening tag is found), and a function prototype for the end element handler (to be called when an

xml_set_element_handler example

if (empty($options['useId'])) {
            $this->_useId = false;
        } else {
            $this->_useId = true;
        }

        $encoding      = $this->_findEncoding($filename);
        $this->_target = $locale;
        $this->_file   = xml_parser_create($encoding);
        xml_set_object($this->_file, $this);
        xml_parser_set_option($this->_file, XML_OPTION_CASE_FOLDING, 0);
        xml_set_element_handler($this->_file, "_startElement", "_endElement");
        xml_set_character_data_handler($this->_file, "_contentElement");

        if (!xml_parse($this->_file, file_get_contents($filename))) {
            $ex = sprintf('XML error: %s at line %d of file %s',
                          xml_error_string(xml_get_error_code($this->_file)),
                          xml_get_current_line_number($this->_file),
                          $filename);
            xml_parser_free($this->_file);
            throw new Zend_Translate_Exception($ex);
        }

$xml_is_sane = isset($values[0]['value']);
        }

        // Create the parser         if ($xml_is_sane)
        {
            $xml = xml_parser_create_ns($this->encoding, $this->separator);
            xml_parser_set_option($xml, XML_OPTION_SKIP_WHITE, 1);
            xml_parser_set_option($xml, XML_OPTION_CASE_FOLDING, 0);
            xml_set_object($xml, $this);
            xml_set_character_data_handler($xml, 'cdata');
            xml_set_element_handler($xml, 'tag_open', 'tag_close');

            // Parse!             $wrapper = @is_writable(sys_get_temp_dir()) ? 'php://temp' : 'php://memory';
            if (($stream = fopen($wrapper, 'r+')) &&
                fwrite($stream, $data) &&
                rewind($stream))
            {
                //Parse by chunks not to use too much memory                 do
                {
                    $stream_data = fread($stream, 1048576);

throw new Zend_Translate_Exception('Translation file \'' . $filename . '\' is not readable.');
        }

        if (isset($options['useId'])) {
            $this->_useId = (boolean) $options['useId'];
        }

        $encoding = $this->_findEncoding($filename);
        $this->_file = xml_parser_create($encoding);
        xml_set_object($this->_file, $this);
        xml_parser_set_option($this->_file, XML_OPTION_CASE_FOLDING, 0);
        xml_set_element_handler($this->_file, "_startElement", "_endElement");
        xml_set_character_data_handler($this->_file, "_contentElement");

        if (!xml_parse($this->_file, file_get_contents($filename))) {
            $ex = sprintf('XML error: %s at line %d of file %s',
                          xml_error_string(xml_get_error_code($this->_file)),
                          xml_get_current_line_number($this->_file),
                          $filename);
            xml_parser_free($this->_file);
            throw new Zend_Translate_Exception($ex);
        }

set_error_handler(array(&$this, 'error_handler'));

        array_unshift($this->ns_contexts, array());

        if ( ! function_exists( 'xml_parser_create_ns' ) ) {
            trigger_error( __( "PHP's XML extension is not available. Please contact your hosting provider to enable PHP's XML extension." ) );
            return false;
        }

        $parser = xml_parser_create_ns();
        xml_set_object($parser, $this);
        xml_set_element_handler($parser, "start_element", "end_element");
        xml_parser_set_option($parser,XML_OPTION_CASE_FOLDING,0);
        xml_parser_set_option($parser,XML_OPTION_SKIP_WHITE,0);
        xml_set_character_data_handler($parser, "cdata");
        xml_set_default_handler($parser, "_default");
        xml_set_start_namespace_decl_handler($parser, "start_ns");
        xml_set_end_namespace_decl_handler($parser, "end_ns");

        $this->content = '';

        $ret = true;

$this->_data = array();
        if (!is_readable($filename)) {
            throw new Zend_Translate_Exception('Translation file \'' . $filename . '\' is not readable.');
        }

        $this->_target = $locale;

        $encoding = $this->_findEncoding($filename);
        $this->_file = xml_parser_create($encoding);
        xml_set_object($this->_file, $this);
        xml_parser_set_option($this->_file, XML_OPTION_CASE_FOLDING, 0);
        xml_set_element_handler($this->_file, "_startElement", "_endElement");
        xml_set_character_data_handler($this->_file, "_contentElement");

        if (!xml_parse($this->_file, file_get_contents($filename))) {
            $ex = sprintf('XML error: %s at line %d of file %s',
                          xml_error_string(xml_get_error_code($this->_file)),
                          xml_get_current_line_number($this->_file),
                          $filename);
            xml_parser_free($this->_file);
            throw new Zend_Translate_Exception($ex);
        }

// Create an XML parser. if ( ! function_exists( 'xml_parser_create' ) ) {
    trigger_error( __( "PHP's XML extension is not available. Please contact your hosting provider to enable PHP's XML extension." ) );
    wp_die( __( "PHP's XML extension is not available. Please contact your hosting provider to enable PHP's XML extension." ) );
}

$xml_parser = xml_parser_create();

// Set the functions to handle opening and closing tags. xml_set_element_handler( $xml_parser, 'startElement', 'endElement' );

if ( ! xml_parse( $xml_parser, $opml, true ) ) {
    printf(
        /* translators: 1: Error message, 2: Line number. */
        __( 'XML Error: %1$s at line %2$s' ),
        xml_error_string( xml_get_error_code( $xml_parser ) ),
        xml_get_current_line_number( $xml_parser )
    );
}

// Free up memory used by the XML parser.

return trigger_error( "PHP's XML extension is not available. Please contact your hosting provider to enable PHP's XML extension." );
        }

        $parser = xml_parser_create();

        $this->parser = $parser;

        # pass in parser, and a reference to this object         # set up handlers         #         xml_set_object( $this->parser, $this );
        xml_set_element_handler($this->parser,
                'feed_start_element', 'feed_end_element' );

        xml_set_character_data_handler( $this->parser, 'feed_cdata' );

        $status = xml_parse( $this->parser, $source );

        if (! $status ) {
            $errorcode = xml_get_error_code( $this->parser );
            if ( $errorcode != XML_ERROR_NONE ) {
                $xml_error = xml_error_string( $errorcode );
                $error_line = xml_get_current_line_number($this->parser);

protected function _loadTranslationData($filename, $locale, array $options = array())
    {
        $this->_data = array();
        if (!is_readable($filename)) {
            throw new Zend_Translate_Exception('Translation file \'' . $filename . '\' is not readable.');
        }

        $encoding = $this->_findEncoding($filename);
        $this->_file = xml_parser_create($encoding);
        xml_set_object($this->_file, $this);
        xml_parser_set_option($this->_file, XML_OPTION_CASE_FOLDING, 0);
        xml_set_element_handler($this->_file, "_startElement", "_endElement");
        xml_set_character_data_handler($this->_file, "_contentElement");

        if (!xml_parse($this->_file, file_get_contents($filename))) {
            $ex = sprintf('XML error: %s at line %d of file %s',
                          xml_error_string(xml_get_error_code($this->_file)),
                          xml_get_current_line_number($this->_file),
                          $filename);
            xml_parser_free($this->_file);
            throw new Zend_Translate_Exception($ex);
        }

$element_limit = apply_filters( 'xmlrpc_element_limit', $element_limit );
        }
        if ( $element_limit && 2 * $element_limit < substr_count( $this->message, '<' ) ) {
            return false;
        }

        $this->_parser = xml_parser_create();
        // Set XML parser to take the case of tags in to account         xml_parser_set_option($this->_parser, XML_OPTION_CASE_FOLDING, false);
        // Set XML parser callback functions         xml_set_object($this->_parser, $this);
        xml_set_element_handler($this->_parser, 'tag_open', 'tag_close');
        xml_set_character_data_handler($this->_parser, 'cdata');

        // 256Kb, parse in chunks to avoid the RAM usage on very large messages         $chunk_size = 262144;

        /** * Filters the chunk size that can be used to parse an XML-RPC response message. * * @since 4.4.0 * * @param int $chunk_size Chunk size to parse in bytes. */

        $this->_data = array();
        $this->_lang = $locale;
        if (!is_readable($filename)) {
            throw new Zend_Translate_Exception('Translation file \'' . $filename . '\' is not readable.');
        }

        $encoding    = $this->_findEncoding($filename);
        $this->_file = xml_parser_create($encoding);
        xml_set_object($this->_file, $this);
        xml_parser_set_option($this->_file, XML_OPTION_CASE_FOLDING, 0);
        xml_set_element_handler($this->_file, "_startElement", "_endElement");
        xml_set_character_data_handler($this->_file, "_contentElement");

        if (!xml_parse($this->_file, file_get_contents($filename))) {
            $ex = sprintf('XML error: %s at line %d of file %s',
                          xml_error_string(xml_get_error_code($this->_file)),
                          xml_get_current_line_number($this->_file),
                          $filename);
            xml_parser_free($this->_file);
            throw new Zend_Translate_Exception($ex);
        }