Resource Types
Found this in the IXmlReader docs at msdn but it's also valid for XMLReader in PHP.
You should save the value of $isEmptyElement before processing attributes, or call moveToElement to make $isEmptyElement valid after processing attributes.
$isEmptyElement returns FALSE when XMLReader is positioned on an attribute node, even if attribute's parent element is empty.
The XMLReader class
Introduction
The XMLReader extension is an XML Pull parser. The reader acts as a cursor going forward on the document stream and stopping at each node on the way.
Class synopsis
XMLReader
{
/* Constants */
/* Properties */
/* Methods */
}Properties
- attributeCount
-
The number of attributes on the node
- baseURI
-
The base URI of the node
- depth
-
Depth of the node in the tree, starting at 0
- hasAttributes
-
Indicates if node has attributes
- hasValue
-
Indicates if node has a text value
- isDefault
-
Indicates if attribute is defaulted from DTD
- isEmptyElement
-
Indicates if node is an empty element tag
- localName
-
The local name of the node
- name
-
The qualified name of the node
- namespaceURI
-
The URI of the namespace associated with the node
- nodeType
-
The node type for the node
- prefix
-
The prefix of the namespace associated with the node
- value
-
The text value of the node
- xmlLang
-
The xml:lang scope which the node resides
Predefined Constants
XMLReader Node Types
- XMLReader::NONE
-
No node type
- XMLReader::ELEMENT
-
Start element
- XMLReader::ATTRIBUTE
-
Attribute node
- XMLReader::TEXT
-
Text node
- XMLReader::CDATA
-
CDATA node
- XMLReader::ENTITY_REF
-
Entity Reference node
- XMLReader::ENTITY
-
Entity Declaration node
- XMLReader::PI
-
Processing Instruction node
- XMLReader::COMMENT
-
Comment node
- XMLReader::DOC
-
Document node
- XMLReader::DOC_TYPE
-
Document Type node
- XMLReader::DOC_FRAGMENT
-
Document Fragment node
- XMLReader::NOTATION
-
Notation node
- XMLReader::WHITESPACE
-
Whitespace node
- XMLReader::SIGNIFICANT_WHITESPACE
-
Significant Whitespace node
- XMLReader::END_ELEMENT
-
End Element
- XMLReader::END_ENTITY
-
End Entity
- XMLReader::XML_DECLARATION
-
XML Declaration node
XMLReader Parser Options
- XMLReader::LOADDTD
-
Load DTD but do not validate
- XMLReader::DEFAULTATTRS
-
Load DTD and default attributes but do not validate
- XMLReader::VALIDATE
-
Load DTD and validate while parsing
- XMLReader::SUBST_ENTITIES
-
Substitute entities and expand references
Table of Contents
- XMLReader::close — بستن ورودی XMLReader
- XMLReader::expand — بازگرداندن کپی گره فعلی شی DOM
- XMLReader::getAttribute — دریافت مقدار ویژگی نامدار
- XMLReader::getAttributeNo — دریافت مقدار ویژگی به وسیله index
- XMLReader::getAttributeNs — دریافت مقدار ویژگی با استفاده از localname و URI
- XMLReader::getParserProperty — نشاندهنده تنظیم شدن خاصیت مشخص شده
- XMLReader::isValid — نشاندهنده صحیح بودن سند
- XMLReader::lookupNamespace — Lookup namespace for a prefix
- XMLReader::moveToAttribute — انتقال cursor به ویژگی نامدار
- XMLReader::moveToAttributeNo — انتقال cursor به یک ویژگی با استفاده از index
- XMLReader::moveToAttributeNs — انتقال cursor به ویژگی نامدار
- XMLReader::moveToElement — انتقال cursor به جز والد در ویژگی فعلی
- XMLReader::moveToFirstAttribute — Position cursor on the first Attribute
- XMLReader::moveToNextAttribute — انتقال cursor به ویژگی بعدی
- XMLReader::next — انتقال cursor به گره بعدی با پرش از تمام زیردرختها
- XMLReader::open — تنظیم URI شامل سند XML مورد پردازش
- XMLReader::read — جابجا نمودن گره بعدی در سند
- XMLReader::readInnerXML — دریافت XML از گره فعلی
- XMLReader::readOuterXML — گرفتن XML از گره فعلی شامل خود
- XMLReader::readString — خواندن محتوای گره فعلی به عنوان رشته
- XMLReader::setParserProperty — تنظیم یا عدم تنظیم گزینههای پارسر
- XMLReader::setRelaxNGSchema — تنظیم filename یا URI برای RelaxNG Schema
- XMLReader::setRelaxNGSchemaSource — تنظیم داده شامل RelaxNG Schema
- XMLReader::setSchema — تایید صحت سند نسبت به XSD
- XMLReader::XML — تنظیم داده شامل XML مورد پردازش
add a note
User Contributed Notes
XMLReader - [16 notes]
kula_shakerz ¶
1 month ago
jart (at) mail.ru ¶
2 years ago
Guys, I hope this example will help
you can erase prints showing the process-
and it will be a piece of nice code.
<?php
function xml2assoc($xml, $name)
{
print "<ul>";
$tree = null;
print("I'm inside " . $name . "<br>");
while($xml->read())
{
if($xml->nodeType == XMLReader::END_ELEMENT)
{
print "</ul>";
return $tree;
}
else if($xml->nodeType == XMLReader::ELEMENT)
{
$node = array();
print("Adding " . $xml->name ."<br>");
$node['tag'] = $xml->name;
if($xml->hasAttributes)
{
$attributes = array();
while($xml->moveToNextAttribute())
{
print("Adding attr " . $xml->name ." = " . $xml->value . "<br>");
$attributes[$xml->name] = $xml->value;
}
$node['attr'] = $attributes;
}
if(!$xml->isEmptyElement)
{
$childs = xml2assoc($xml, $node['tag']);
$node['childs'] = $childs;
}
print($node['tag'] . " added <br>");
$tree[] = $node;
}
else if($xml->nodeType == XMLReader::TEXT)
{
$node = array();
$node['text'] = $xml->value;
$tree[] = $node;
print "text added = " . $node['text'] . "<br>";
}
}
print "returning " . count($tree) . " childs<br>";
print "</ul>";
return $tree;
}
echo "<PRE>";
$xml = new XMLReader();
$xml->open('test.xml');
$assoc = xml2assoc($xml, "root");
$xml->close();
print_r($assoc);
echo "</PRE>";
?>
It reads this xml:
<test>
<hallo volume="loud"> me <br/> lala </hallo>
<hallo> me </hallo>
</test>
james dot ellis at example dot com ¶
4 years ago
The "XML2Assoc" functions noted here should be used with caution... basically they are duplicating the functionality already present in SimpleXML. They may work but they won't scale.
Their are two main uses cases for parsing XML, each suited to either XMLReader or SimpleXML.
1. SimpleXML is an excellent tool for easy access to an XML document tree using native PHP data types. It starts to flounder with massive (> 50M or so) XML documents, as it reads the entire document into memory before it can be processed. SimpleXML will just laugh at you then die when your server runs out of memory (or it will cause a load spike).
2. Aside from the reasoning behind massive XML documents, if you have to deal with massive XML documents, use XMLReader to process them. Don't try and gather an entire XML document into a PHP data structure using XMLReader and a PHP xml2assoc() function, you are reinventing the SimpleXML wheel.
When parsing massive XML documents using XMLReader, gather the data you need to perform an operation then perform it before skipping to the next node. Do not build massive data structures from a massive XML document, your server (and it's admins) will not like you.
Sergey Aikinkulov ¶
4 years ago
Next version xml2assoc with some improve fixes:
- no doubled data
- no buffer arrays
<?php
/*
Read XML structure to associative array
--
Using:
$xml = new XMLReader();
$xml->open([XML file]);
$assoc = xml2assoc($xml);
$xml->close();
*/
function xml2assoc($xml) {
$assoc = null;
while($xml->read()){
switch ($xml->nodeType) {
case XMLReader::END_ELEMENT: return $assoc;
case XMLReader::ELEMENT:
$assoc[$xml->name][] = array('value' => $xml->isEmptyElement ? '' : xml2assoc($xml));
if($xml->hasAttributes){
$el =& $assoc[$xml->name][count($assoc[$xml->name]) - 1];
while($xml->moveToNextAttribute()) $el['attributes'][$xml->name] = $xml->value;
}
break;
case XMLReader::TEXT:
case XMLReader::CDATA: $assoc .= $xml->value;
}
}
return $assoc;
}
?>
desk_ocean at msn dot com ¶
5 years ago
make some modify from Sergey Aikinkulov's note
<?php
function xml2assoc(&$xml){
$assoc = NULL;
$n = 0;
while($xml->read()){
if($xml->nodeType == XMLReader::END_ELEMENT) break;
if($xml->nodeType == XMLReader::ELEMENT and !$xml->isEmptyElement){
$assoc[$n]['name'] = $xml->name;
if($xml->hasAttributes) while($xml->moveToNextAttribute()) $assoc[$n]['atr'][$xml->name] = $xml->value;
$assoc[$n]['val'] = xml2assoc($xml);
$n++;
}
else if($xml->isEmptyElement){
$assoc[$n]['name'] = $xml->name;
if($xml->hasAttributes) while($xml->moveToNextAttribute()) $assoc[$n]['atr'][$xml->name] = $xml->value;
$assoc[$n]['val'] = "";
$n++;
}
else if($xml->nodeType == XMLReader::TEXT) $assoc = $xml->value;
}
return $assoc;
}
?>
add else if($xml->isEmptyElement)
may be some xml has emptyelement
Mike De Smet ¶
7 months ago
For those of you getting xml files that do not contain duplicate elements (in the same element), the following converter converts to arrays with key/value mapping (thus overwriting duplicate elements!):
Note this is untested with attributes although I built in support.
<?php
function xml2assoc($xml, array &$target = array()) {
while ($xml->read()) {
switch ($xml->nodeType) {
case XMLReader::END_ELEMENT:
return $target;
case XMLReader::ELEMENT:
$name = $xml->name;
$target[$name] = $xml->hasAttributes ? array() : '';
if (!$xml->isEmptyElement) {
$target[$name] = array();
xml2assoc($xml, $target[$name]);
}
if ($xml->hasAttributes)
while($xml->moveToNextAttribute())
$target[$name]['@'.$xml->name] = $xml->value;
break;
case XMLReader::TEXT:
case XMLReader::CDATA:
$target = $xml->value;
}
}
return $target;
}
?>
casella dot email at google dot mail dot com ¶
8 months ago
To verify that all nodes are read without error/warning you can use this code:
<?php
$endofxml = false;
$xml_url = "example.xml";
$reader = new XMLReader();
if(!$reader->open($xml_url)){
print "Error to open XML: $xml_url\n";
} else {
while ($reader->read()) {
$firstnode = (!isset($firstnode)) ? $reader->name : $firstnode;
/*
DO SOMETHING
*/
if ($reader->nodeType == XMLReader::END_ELEMENT && $reader->name == $firstnode) {
$endofxml = true;
}
}
}
if($endofxml) {
print "no error found";
} else {
print "error found";
}
?>
This code is useful to trap $reader->read() error/warning.
lee8oi at gmail dot com ¶
1 year ago
Sometimes you have an unusual URL that doesn't actually point to an xml file but still returns xml as output (Like the Battlefield Heroes generated syndication urls). Using get_file_contents(url) you can retrieve the xml data from these urls and pass it as a variable for processing as an XML String.
Unfortunately simpleXML or xml DOM cannot process all xml strings. Some have error boxes added to the end of them (such as Battlefield Heroes syndicated news). These boxes cause an end of file sort of error and closes out the script. XMLReader grabs data from these strings without error.
japos dot trash at googlemail dot com ¶
2 years ago
Take care about how to use XMLReader::$isElementEmpty. I don't know if it is a bug or not, but $isElementEmpty is set for the current context and NOT just for the element. If you move your cursor to an attribute, $isElementEmpty will ALWAYS be false.
<?php
$xml = new XMLReader();
$xml->XML('<tag attr="value" />');
$xml->read();
var_dump($xml->isEmptyElement);
$xml->moveToNextAttribute();
var_dump($xml->isEmptyElement);
?>
will output
(bool) true
(bool) false
So be sure to store $isEmptyElement before moving the cursor.
jnettles at inccrra dot org ¶
3 years ago
Just in case someone is confused, if you're wanting to simply pass a string of XML instead of an entire file, you would do this.
<?php
$foo = new XMLReader();
$foo->xml($STRING);
?>
.... where $STRING holds your XML. You cannot pass it like $foo = $STRING or $foo->xml = $STRING.
PxL ¶
4 years ago
A basic parser
<?php
function xml2assoc($xml) {
$arr = array();
if (!preg_match_all('|\<\s*?(\w+).*?\>(.*)\<\/\s*\\1.*?\>|s', $xml, $m)) return $xml;
if (is_array($m[1]))
for ($i = 0;$i < sizeof($m[1]); $i++) $arr[$m[1][$i]] = xml2assoc($m[2][$i]);
else $arr[$m[1]] = xml2assoc($m[2]);
return $arr;
}
?>
boukeversteegh at gmail dot com ¶
4 years ago
XML to ASSOCIATIVE ARRAY
Improved algorithm based on Sergey Aikinkulov's. The problem was that it would overwrite nodes if they had the same tag name. Because of that <a><b/><b/><a> would be read as if <a><b/><a/>. This algorithm handles it better and outputs an easy to understand array:
<?php
function xml2assoc($xml) {
$tree = null;
while($xml->read())
switch ($xml->nodeType) {
case XMLReader::END_ELEMENT: return $tree;
case XMLReader::ELEMENT:
$node = array('tag' => $xml->name, 'value' => $xml->isEmptyElement ? '' : xml2assoc($xml));
if($xml->hasAttributes)
while($xml->moveToNextAttribute())
$node['attributes'][$xml->name] = $xml->value;
$tree[] = $node;
break;
case XMLReader::TEXT:
case XMLReader::CDATA:
$tree .= $xml->value;
}
return $tree;
}
?>
Usage:
myxml.xml:
------
<PERSON>
<NAME>John</NAME>
<PHONE type="home">555-555-555</PHONE>
</PERSON>
----
<?
$xml = new XMLReader();
$xml->open('myxml.xml');
$assoc = xml2assoc($xml);
$xml->close();
print_r($assoc);
?>
Outputs:
Array
(
[0] => Array
(
[tag] => PERSON
[value] => Array
(
[0] => Array
(
[tag] => NAME
[value] => John
)
[1] => Array
(
[tag] => PHONE
[value] => 555-555-555
[attributes] => Array
(
[type] => home
)
)
)
)
)
For reasons that have to do with recursion, it returns an array with the ROOT xml node as the first childNode, rather than to return only the ROOT node.
andrei_antal at yahoo dot com ¶
4 years ago
<?php
//Pull certain elements
$reader = new XMLReader();
$reader->open($xmlfile);
while ($reader->read()) {
switch ($reader->nodeType) {
case (XMLREADER::ELEMENT):
if ($reader->name == "Code")
{
$reader->read();
$code = trim($reader->value);
echo "$code\n";
break;
}
if ($reader->name == "Name")
{
$reader->read();
$customername = trim( $reader->value );
echo "$name\n";
break;
}
if ($reader->name == "Camp")
{
$camp = trim($reader->getAttribute("ID"));
echo "$camp\n";
break;
}
}
}
?>
godseth at o2 dot pl ¶
4 years ago
Thanks rein_baarsma33 AT hotmail DOT com for bugfixes.
This is my new child of XML parsing method based on my and yours modification.
XML2ASSOC Is a complete solution for parsing ordinary XML
<?php
/**
* XML2Assoc Class to creating
* PHP Assoc Array from XML File
*
* @author godseth (AT) o2.pl & rein_baarsma33 (AT) hotmail.com (Bugfixes in parseXml Method)
* @uses XMLReader
*
*/
class Xml2Assoc {
/**
* Optimization Enabled / Disabled
*
* @var bool
*/
protected $bOptimize = false;
/**
* Method for loading XML Data from String
*
* @param string $sXml
* @param bool $bOptimize
*/
public function parseString( $sXml , $bOptimize = false) {
$oXml = new XMLReader();
$this -> bOptimize = (bool) $bOptimize;
try {
// Set String Containing XML data
$oXml->XML($sXml);
// Parse Xml and return result
return $this->parseXml($oXml);
} catch (Exception $e) {
echo $e->getMessage();
}
}
/**
* Method for loading Xml Data from file
*
* @param string $sXmlFilePath
* @param bool $bOptimize
*/
public function parseFile( $sXmlFilePath , $bOptimize = false ) {
$oXml = new XMLReader();
$this -> bOptimize = (bool) $bOptimize;
try {
// Open XML file
$oXml->open($sXmlFilePath);
// // Parse Xml and return result
return $this->parseXml($oXml);
} catch (Exception $e) {
echo $e->getMessage(). ' | Try open file: '.$sXmlFilePath;
}
}
/**
* XML Parser
*
* @param XMLReader $oXml
* @return array
*/
protected function parseXml( XMLReader $oXml ) {
$aAssocXML = null;
$iDc = -1;
while($oXml->read()){
switch ($oXml->nodeType) {
case XMLReader::END_ELEMENT:
if ($this->bOptimize) {
$this->optXml($aAssocXML);
}
return $aAssocXML;
case XMLReader::ELEMENT:
if(!isset($aAssocXML[$oXml->name])) {
if($oXml->hasAttributes) {
$aAssocXML[$oXml->name][] = $oXml->isEmptyElement ? '' : $this->parseXML($oXml);
} else {
if($oXml->isEmptyElement) {
$aAssocXML[$oXml->name] = '';
} else {
$aAssocXML[$oXml->name] = $this->parseXML($oXml);
}
}
} elseif (is_array($aAssocXML[$oXml->name])) {
if (!isset($aAssocXML[$oXml->name][0]))
{
$temp = $aAssocXML[$oXml->name];
foreach ($temp as $sKey=>$sValue)
unset($aAssocXML[$oXml->name][$sKey]);
$aAssocXML[$oXml->name][] = $temp;
}
if($oXml->hasAttributes) {
$aAssocXML[$oXml->name][] = $oXml->isEmptyElement ? '' : $this->parseXML($oXml);
} else {
if($oXml->isEmptyElement) {
$aAssocXML[$oXml->name][] = '';
} else {
$aAssocXML[$oXml->name][] = $this->parseXML($oXml);
}
}
} else {
$mOldVar = $aAssocXML[$oXml->name];
$aAssocXML[$oXml->name] = array($mOldVar);
if($oXml->hasAttributes) {
$aAssocXML[$oXml->name][] = $oXml->isEmptyElement ? '' : $this->parseXML($oXml);
} else {
if($oXml->isEmptyElement) {
$aAssocXML[$oXml->name][] = '';
} else {
$aAssocXML[$oXml->name][] = $this->parseXML($oXml);
}
}
}
if($oXml->hasAttributes) {
$mElement =& $aAssocXML[$oXml->name][count($aAssocXML[$oXml->name]) - 1];
while($oXml->moveToNextAttribute()) {
$mElement[$oXml->name] = $oXml->value;
}
}
break;
case XMLReader::TEXT:
case XMLReader::CDATA:
$aAssocXML[++$iDc] = $oXml->value;
}
}
return $aAssocXML;
}
/**
* Method to optimize assoc tree.
* ( Deleting 0 index when element
* have one attribute / value )
*
* @param array $mData
*/
public function optXml(&$mData) {
if (is_array($mData)) {
if (isset($mData[0]) && count($mData) == 1 ) {
$mData = $mData[0];
if (is_array($mData)) {
foreach ($mData as &$aSub) {
$this->optXml($aSub);
}
}
} else {
foreach ($mData as &$aSub) {
$this->optXml($aSub);
}
}
}
}
}
?>
[EDIT BY danbrown AT php DOT net: Fixes were also provided by "Alex" and (qdog AT qview DOT org) in user notes on this page (since removed).]
orion at ftf-hq dot dk ¶
7 years ago
Some more documentation (i.e. examples) would be nice :-)
This is how I read some mysql parameters in an xml file:
<?php
$xml = new XMLReader();
$xml->open("config.xml");
$xml->setParserProperty(2,true); // This seems a little unclear to me - but it worked :)
while ($xml->read()) {
switch ($xml->name) {
case "mysql_host":
$xml->read();
$conf["mysql_host"] = $xml->value;
$xml->read();
break;
case "mysql_username":
$xml->read();
$conf["mysql_user"] = $xml->value;
$xml->read();
break;
case "mysql_password":
$xml->read();
$conf["mysql_pass"] = $xml->value;
$xml->read();
break;
case "mysql_database":
$xml->read();
$conf["mysql_db"] = $xml->value;
$xml->read();
break;
}
}
$xml->close();
?>
The XML file used:
<?xml version='1.0'?>
<MySQL_INIT>
<mysql_host>localhost</mysql_host>
<mysql_database>db_database</mysql_database>
<mysql_username>root</mysql_username>
<mysql_password>password</mysql_password>
</MySQL_INIT>
itari ¶
5 years ago
<?php
function parseXML($node,$seq,$path) {
global $oldpath;
if (!$node->read())
return;
if ($node->nodeType != 15) {
print '<br/>'.$node->depth;
print '-'.$seq++;
print ' '.$path.'/'.($node->nodeType==3?'text() = ':$node->name);
print $node->value;
if ($node->hasAttributes) {
print ' [hasAttributes: ';
while ($node->moveToNextAttribute()) print '@'.$node->name.' = '.$node->value.' ';
print ']';
}
if ($node->nodeType == 1) {
$oldpath=$path;
$path.='/'.$node->name;
}
parseXML($node,$seq,$path);
}
else parseXML($node,$seq,$oldpath);
}
$source = "<tag1>this<tag2 id='4' name='foo'>is</tag2>a<tag2 id='5'>common</tag2>record</tag1>";
$xml = new XMLReader();
$xml->XML($source);
print htmlspecialchars($source).'<br/>';
parseXML($xml,0,'');
?>
Output:
<tag1>this<tag2 id='4' name='foo'>is</tag2>a<tag2 id='5'>common</tag2>record</tag1>
0-0 /tag1
1-1 /tag1/text() = this
1-2 /tag1/tag2 [hasAttributes: @id = 4 @name = foo ]
2-3 /tag1/text() = is
1-4 /text() = a
1-5 /tag2 [hasAttributes: @id = 5 ]
2-6 /text() = common
1-7 /text() = record