The SimpleXMLIterator class

(PHP 5 >= 5.1.3, PHP 7, PHP 8)

简介

The SimpleXMLIterator provides recursive iteration over all nodes of a SimpleXMLElement object.

类摘要

SimpleXMLIterator extends SimpleXMLElement implements RecursiveIterator , Countable {
/* 方法 */
public current ( ) : mixed
public getChildren ( ) : SimpleXMLIterator
public hasChildren ( ) : bool
public key ( ) : mixed
public next ( ) : void
public rewind ( ) : void
public valid ( ) : bool
/* 继承的方法 */
public SimpleXMLElement::__construct ( string $data , int $options = 0 , bool $dataIsURL = false , string $namespaceOrPrefix = "" , bool $isPrefix = false )
public SimpleXMLElement::addAttribute ( string $qualifiedName , string $value , string|null $namespace = null ) : void
public SimpleXMLElement::addChild ( string $qualifiedName , string|null $value = null , string|null $namespace = null ) : SimpleXMLElement|null
public SimpleXMLElement::asXML ( string|null $filename = null ) : string|bool
public SimpleXMLElement::attributes ( string|null $namespaceOrPrefix = null , bool $isPrefix = false ) : SimpleXMLElement|null
public SimpleXMLElement::children ( string|null $namespaceOrPrefix = null , bool $isPrefix = false ) : SimpleXMLElement|null
public SimpleXMLElement::count ( ) : int
public SimpleXMLElement::getDocNamespaces ( bool $recursive = false , bool $fromRoot = true ) : array|false
public SimpleXMLElement::getName ( ) : string
public SimpleXMLElement::getNamespaces ( bool $recursive = false ) : array
public SimpleXMLElement::registerXPathNamespace ( string $prefix , string $namespace ) : bool
public SimpleXMLElement::__toString ( ) : string
public SimpleXMLElement::xpath ( string $expression ) : array|null|false
}

Table of Contents

User Contributed Notes

prouchetvincent at free dot fr 10-Oct-2020 12:47
<?php
=======================================================
$index =
<?xml version="1.0" encoding="UTF-8"?>
<root>
    <article id="8" visibility="true" filename="2020-10-08" fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
    <article id="7" visibility="true" filename="2020-10-07" fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
    <article id="6" visibility="true" filename="2020-10-02" fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
    <article id="5" visibility="true" filename="2020-09-30" fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
    <article id="4" visibility="true" filename="2020-09-26" fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
    <article id="3" visibility="true" filename="2020-09-22"     fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
    <article id="2" visibility="true" filename="2020-09-20"     fileExtension="xml">
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
        <article id="1" visibility="true" filename="hello world" fileExtension="xml">
            Hello World
            <tag>xml</tag>
            <tag>php</tag>
            <tag>experiment</tag>       
    </article>
</root>
====================================================================
?>
If you have to use an iterator to parse your XML
and need tu get an attribute of tags of this iterator then
use the fonction
->current()
of simpleXMLIterator on your object before
->attributes()->{attibute name}
<?php
$file="";
try{
     $index = new SimpleXMLIterator ( file_get_contents ( FILEDIRECTORY. 'index.xml' ) );}
catch(Exception $e) {whatever you want to do on error}}

for( $index->rewind(); $index->valid(); $index->next() ) {
    try {
          $file = file_get_contents(FILESDIRECTORY.$index->current()->attributes()->{'fileName'}. '.xml' );
    } catch (Exception $e) {whatever you want to do on error}
    $article = new Article ();
    $article->setXMLArticle ($file);
    array_push( $this->articles, $article );
    $file ="";
    }
}
?>
This exemple use a custom made Article object that itself parse the file given to him to initialise its properties .
Here we open a file (Yes I use constant for my directories)
make it a simpleXMLIterator and parse article elements to get the filename attribute to use it to open another XML file for data collection.
don't forget !!! In PHP Object created by new ClassName() are ALWAYS given by reference that is why new Article() in inside the loop and not outside
(yhea, I did that mistake)
XMLIterator are powerfull yet harder to understand in themselves but once passed that one point.
They are very more easier to use than plain arrays.
rukkykf at gmail dot com 16-Dec-2018 06:54
I think it's worth mentioning that you need to call the rewind() method on the SimpleXMLIterator object immediately after initialization before you can start doing any other operations on the object. An example:

<?php
$xml = new SimpleXMLIterator('file.xml', null, true);

// $x here will be set to null because the rewind() method has not been called
$x = $xml->current();

$xml->rewind();

// $x here will be set to the first element
$x = $xml->current();

?>
php-lover at live dot com 05-Oct-2015 09:50
Function to extract SimpleXMLElement data to array.

function extract($sxe = null) {
    if (!$sxe instanceOf SimpleXMLElement)
        return array();

    $extract = array();

    foreach ($sxe->children() as $key => $value) {
        if (array_key_exists($key, $extract)) {
            if (!isset($extract[$key][0])) {
                $tmp_extract = $extract[$key];
                $extract[$key] = array();
                $extract[$key][0] = $tmp_extract;
            } else
                $extract[$key] = (array) $extract[$key];
        }

        if ($value->count()) {
            if (isset($extract[$key]) && is_array($extract[$key]))
                $extract[$key][] = $this->extract($value);
            else
                $extract[$key] = $this->extract($value);
        } else {
            if (isset($extract[$key]) && is_array($extract[$key]))
                $extract[$key][] = empty(strval($value)) ? null : strval($value);
            else
                $extract[$key] = empty(strval($value)) ? null : strval($value);
        }
    }

    return $extract;
}
centy2010 at hotmail dot com 16-Jul-2014 03:22
I filled my database from an XML file about 1260 Kb.
I made my process less than a second. Simply by using SimpleXML.

I give you a little example of the usage to fill a database.
Given the table universe.
With 4 columns Coords, Planet_Name, Player_id, Moon_Size.

Now You have a XML file named universe.xml with this kind of data.
I enclose the data within php tags but it's a file :p
<?php
$xml = <<<EOT
<?xml version="1.0" encoding="UTF-8"?>
<universe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" -
xsi:noNamespaceSchemaLocation="http://s127-fr.ogame.gameforge.com/api/xsd/universe.xsd" -
timestamp="1405413350" serverId="fr127">
    <planet id="1" player="1" name="Arakis" coords="1:1:2">
        <moon id="2" name="Mond" size="4998"/>
    </planet>
    <planet id="33620176" player="100000" name="GameAdmin" coords="1:1:3"/>
    <planet id="33620179" player="100003" name="Heimatplanet" coords="1:1:1"/>
    <planet id="33620186" player="100004" name="OGame Team" coords="6:250:1"/>
    <planet id="33620242" player="100058" name="KnS" coords="9:1:6">
        <moon id="33668391" name="Lune" size="8831"/>
    </planet>
</universe>
EOT;
?>

Now how to bring these data in my 4 columns table :

<?php
$newfname = $path."Universe.XML";
$mydata = new SimpleXmlIterator($newfname, 0, true);
$myquery = "INSERT INTO `".$tablename."` (`coords`,`planet_name`, `player_id`, `moon_size`) VALUES ";
for ($mydata->rewind();$mydata->valid();$mydata->next()) {
    $myquery.= " ('".$mydata->current()->attributes()['coords']
_."','".utf8_decode($mydata->current()->attributes()['name'])
_."','".utf8_decode($mydata->current()->attributes()['player'])
_."','";
    if ($mydata->haschildren()) {
        $myquery.= $mydate->current()->children()->attributes()['size']."'),";
    } else {
        $myquery.= "'),";
    }
}
$myquery = rtrim($myquery, ",");
$datatosql = mysql_query($myquery);
?>
hezll at msn dot com 11-Apr-2013 04:34
Most of the time we need to convert the XML to array or JSON , but now I have to completed the requirement of converting XML to XPath which make our template easily geting the data from XML data source due to the Xpath mapping .Here is the function:

<?php

function sxiToXpath($sxi, $key = null, &$tmp = null)
{
    $keys_arr = array();
    //get the keys count array
    for ($sxi->rewind(); $sxi->valid(); $sxi->next())
    {
        $sk = $sxi->key();
        if (array_key_exists($sk, $keys_arr))
        {
            $keys_arr[$sk]+=1;
            $keys_arr[$sk] = $keys_arr[$sk];
        }
        else
        {
            $keys_arr[$sk] = 1;
        }
    }
    //create the xpath
    for ($sxi->rewind(); $sxi->valid(); $sxi->next())
    {
        $sk = $sxi->key();
        if (!isset($$sk))
        {
            $$sk = 1;
        }
        if ($keys_arr[$sk] >= 1)
        {
            $spk = $sk . '[' . $$sk . ']';
            $keys_arr[$sk] = $keys_arr[$sk] - 1;
            $$sk++;
        }
        else
        {
            $spk = $sk;
        }
        $kp = $key ? $key . '/' . $spk : '/' . $sxi->getName() . '/' . $spk;
        if ($sxi->hasChildren())
        {
            sxiToXpath($sxi->getChildren(), $kp, $tmp);
        }
        else
        {
            $tmp[$kp] = strval($sxi->current());
        }
        $at = $sxi->current()->attributes();
        if ($at)
        {
            $tmp_kp = $kp;
            foreach ($at as $k => $v)
            {
                $kp .= '/@' . $k;
                $tmp[$kp] = $v;
                $kp = $tmp_kp;
            }
        }
    }
    return $tmp;
}

function xmlToXpath($xml)
{
    $sxi = new SimpleXmlIterator($xml);
    return sxiToXpath($sxi);
}

/**
 *  How to use the function
 */
$xml = <<<EOT
<?xml version="1.0" encoding="utf8" ?>       
<data>
   <item ID="30001">
      <Company>Navarro Corp.</Company>
   </item>
   <item ID="30002" IDd="30002">
      <Company>Performant Systems</Company>
   </item>
   <item ID="30003">
      <Company id='id_test'><g id='id_g'>glove</g></Company>   
   </item>
    <item>
    </item>
</data>
EOT;

$rs = xmlToXpath($xml);
print_r($rs);

/**
 * the results may lkie this:
Array
(
    [/data/item[1]/Company[1]] => Navarro Corp.
    [/data/item[1]/@ID] => SimpleXMLIterator Object
        (
            [0] => 30001
        )
    [/data/item[2]/Company[1]] => Performant Systems
    [/data/item[2]/@ID] => SimpleXMLIterator Object
        (
            [0] => 30002
        )

    [/data/item[2]/@IDd] => SimpleXMLIterator Object
        (
            [0] => 30002
        )

    [/data/item[3]/Company[1]/g[1]] => glove
    [/data/item[3]/Company[1]/g[1]/@id] => SimpleXMLIterator Object
        (
            [0] => id_g
        )

    [/data/item[3]/Company[1]/@id] => SimpleXMLIterator Object
        (
            [0] => id_test
        )

    [/data/item[3]/@ID] => SimpleXMLIterator Object
        (
            [0] => 30003
        )

    [/data/item[4]] =>
   
)
 */

echo "Total:" . count($rs);

echo "<hr>";
/* You can check the xpath result like this */
$xml = new SimpleXMLElement($xml);
foreach ($rs as $k => $v)
{
    echo "Xpath:" . $k . " |Value:" . $v . " ";
    var_dump($xml->xpath($k));
    echo "<br>";
}
ajnsit dot NOSPAM at gmail dot com 17-Mar-2011 10:14
Here's a simple function to convert an XML string to an array -

<?php
// PHP5.3 and above only
function parse($str) {
    $f = function($iter) {
      foreach($iter as $key=>$val)
        $arr[$key][] = ($iter->hasChildren())?
          call_user_func (__FUNCTION__, $val)
          : strval($val);
      return $arr;
    };
    return $f(new SimpleXmlIterator($str, null));
}
?>

PHP 5.2 and below do not have anonymous functions.
But you can create a helper function to achieve the same thing -

<?php
  function parse($str) {
    return parseHelper(new SimpleXmlIterator($str, null));
  }
  function parseHelper($iter) {
    foreach($iter as $key=>$val)
      $arr[$key][] = ($iter->hasChildren())?
        call_user_func (__FUNCTION__, $val)
        : strval($val);
    return $arr;
  }
?>

Using it is straightforward enough -

<?php

$xml = '
<movies>
  <movie>abcd</movie>
  <movie>efgh</movie>
  <movie>hijk</movie>
</movies>';
var_dump(parse($xml));

?>

This will output -

array
  'movie' =>
    array
      0 => string 'abcd' (length=4)
      1 => string 'efgh' (length=4)
      2 => string 'hijk' (length=4)
ratfactor at gmail dot com 19-Jul-2009 05:08
The documentation is a bit sparse for SimpleXmlIterator.  Here is an example showing the use of its methods. xml2Array and sxiToArray work together to convert an XML document to an associative array structure.

The contents of cats.xml:
======================================
<cats>
  <cat>
      <name>Jack</name>
      <age>2</age>
      <color>grey</color>
      <color>white</color>
  </cat>
  <cat>
      <name>Maxwell</name>
      <age>12</age>
      <color>orange</color>
      <color>black</color>
  </cat>
</cats>
======================================

<?php
function xml2array($fname){
  $sxi = new SimpleXmlIterator($fname, null, true);
  return sxiToArray($sxi);
}

function sxiToArray($sxi){
  $a = array();
  for( $sxi->rewind(); $sxi->valid(); $sxi->next() ) {
    if(!array_key_exists($sxi->key(), $a)){
      $a[$sxi->key()] = array();
    }
    if($sxi->hasChildren()){
      $a[$sxi->key()][] = sxiToArray($sxi->current());
    }
    else{
      $a[$sxi->key()][] = strval($sxi->current());
    }
  }
  return $a;
}

// Read cats.xml and print the results:
$catArray = xml2array('cats.xml');
print_r($catArray);
?>

Results (reformatted a bit for compactness and clarity):
======================================
Array(
  [cat] => Array(
    [0] => Array(
      [name] => Array(  [0] => Jack    )
      [age] => Array(   [0] => 2       )
      [color] => Array( [0] => grey,
                        [1] => white   )
    )
    [1] => Array(
      [name] => Array(  [0] => Maxwell )
      [age] => Array(   [0] => 12      )
      [color] => Array( [0] => orange
                        [1] => black   )
    )
  )
)