xml_parser_create - PHP code example

PHP Function XML Parser Create

The php function xml_parser_create creates an XML parser. This can be used to parse XML data in a variety of ways, for example, to extract information from an XML file, to transform XML into another format, or to validate XML against a schema. The XML parser is used by other XML functions, which will send a document to the parser and get back a list of index data if they are successful or a set of errors if not.

The parser must be freed after use with the xml_parser_free() function. This will return the reference handle you get from xml_parser_create() and frees up any memory the parser was using. This is not strictly necessary, as PHP will clean up unused XML parsers for you, but it's good practice to avoid leaving a resource dangling.

XML is a structured language for data that uses tags to identify the document's content and structure. It's used in a wide range of web technologies, including RSS feeds and Podcasts. XML documents are stored in memory as a Tree structure, and to manipulate them you need an XML parser.

The xml_parser_create() function creates an XML parser and returns a reference handle for use with other XML functions. It can take a parameter that specifies the character encoding for input and output. Possible encodings include ISO-8859-1, UTF-8, and US-ASCII. It also takes an optional namespace support argument, which is a value that can be passed to the other XML parsing functions.

xml_parser_create example

                $this->error_string = 'SimplePie bug! Please report this!';
                return false;
            }
        }

        $return = true;

        static $xml_is_sane = null;
        if ($xml_is_sane === null)
        {
            $parser_check = xml_parser_create();
            xml_parse_into_struct($parser_check, '<foo>&</foo>', $values);
            xml_parser_free($parser_check);
            $xml_is_sane = isset($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);

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

        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);

/** * PHP5 constructor. */
    function __construct( $source ) {

        # Check if PHP xml isn't compiled         #         if ( ! function_exists('xml_parser_create') ) {
            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' );

function endElement( $parser, $tag_name ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionNameInvalid     // Nothing to do. }

// 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 )
    );
}

            $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. */

        $this->_data = array();
        if (!is_readable($filename)) {
            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);

function prep_atom_text_construct( $data ) {
    if ( ! str_contains( $data, '<' ) && ! str_contains( $data, '&' ) ) {
        return array( 'text', $data );
    }

    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." ) );

        return array( 'html', "<![CDATA[$data]]>" );
    }

    $parser = xml_parser_create();
    xml_parse( $parser, '<div>' . $data . '</div>', true );
    $code = xml_get_error_code( $parser );
    xml_parser_free( $parser );
    unset( $parser );

    if ( ! $code ) {
        if ( ! str_contains( $data, '<' ) ) {
            return array( 'text', $data );
        } else {
            $data = "<div xmlns='http://www.w3.org/1999/xhtml'>$data</div>";
            return array( 'xhtml', $data );
        }

    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);

    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.');
        }

        $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);

    protected function _loadTranslationData($filename, $locale, array $options = array())
    {
        $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);

        if (!extension_loaded('xml') || !extension_loaded('pcre'))
        {
            $this->error = 'XML or PCRE extensions not loaded!';
            return false;
        }
        // Then check the xml extension is sane (i.e., libxml 2.7.x issue on PHP < 5.2.9 and libxml 2.7.0 to 2.7.2 on any version) if we don't have xmlreader.         elseif (!extension_loaded('xmlreader'))
        {
            static $xml_is_sane = null;
            if ($xml_is_sane === null)
            {
                $parser_check = xml_parser_create();
                xml_parse_into_struct($parser_check, '<foo>&</foo>', $values);
                xml_parser_free($parser_check);
                $xml_is_sane = isset($values[0]['value']);
            }
            if (!$xml_is_sane)
            {
                return false;
            }
        }

        // The default sanitize class gets set in the constructor, check if it has