Last updated: Fri, 22 Aug 2008

simplexml_load_string

(PHP 5)

simplexml_load_string — Interprets a string of XML into an object

Description

object simplexml_load_string ( string $data [, string $class_name [, int $options [, string $ns [, bool $is_prefix ]]]] )

Takes a well-formed XML string and returns it as an object.

Parameters

data: A well-formed XML string
class_name: You may use this optional parameter so that simplexml_load_string() will return an object of the specified class. That class should extend the SimpleXMLElement class.
options: Since PHP 5.1.0 and Libxml 2.6.0, you may also use the options parameter to specify additional Libxml parameters.
ns
is_prefix

Return Values

Returns an object of class SimpleXMLElement with properties containing the data held within the xml document. On errors, it will return FALSE.

Examples

Example #1 Interpret an XML string


<?php
$string = <<<XML
<?xml version='1.0'?> 
<document>
 <title>Forty What?</title>
 <from>Joe</from>
 <to>Jane</to>
 <body>
  I know that's the answer -- but what's the question?
 </body>
</document>
XML;

$xml = simplexml_load_string($string);

var_dump($xml);
?>

The above example will output:

SimpleXMLElement Object
(
  [title] => Forty What?
  [from] => Joe
  [to] => Jane
  [body] =>
   I know that's the answer -- but what's the question?
)

At this point, you can go about using $xml->body and such.


Theres a problem with the below workaround when serializing fields containing html CDATA. For any other content type then HTML try to modfiy function parseCDATA.

Just add these lines before serializing.

This is also a workaround for this bug http://bugs.php.net/bug.php?id=42001



<?PHP

if(strpos($content, '<![CDATA[')) {

   function parseCDATA($data) {

      return htmlentities($data[1]);

   }

   $content = preg_replace_callback(

      '#<!\[CDATA\[(.*)\]\]>#',

      'parseCDATA',

      str_replace("\n", " ", $content)

   );

}

?>

hattori at hanso dot com
17-Sep-2007 11:15


If you want to serialize and unserialize SimpleXMLElement objects for caching, you need to transform the SimpleXMLElement object into a standard class object before unserializing.

This is only if you want to cache converted data, the functionallity of the SimpleXMLElement will not be held.



$content = '<SomeXML....'



$serialized = str_replace(

  array('O:16:"SimpleXMLElement":0:{}', 'O:16:"SimpleXMLElement":'),

  array('s:0:"";', 'O:8:"stdClass":'),

  serialize(simplexml_load_string($content))

);



$unserialized = unserialize($serialized);

nbijnens at servs dot eu
10-Sep-2007 02:17


Please note that not all LIBXML options are supported with the options argument.



For instance LIBXML_XINCLUDE does not work. But there is however a work around:



<?php

$xml = new DOMDocument();

$xml->loadXML ($XMLString);

            

$xml->xinclude();

$xml = simplexml_import_dom($xml);



?>

Pedro
06-Jul-2007 10:28


Attention:



simplexml_load_string has a problem with entities other than (&lt;, &gt;, &amp;, &quot; and &apos;). 



Use numeric character references instead!

youx_free_fr
23-May-2007 06:52


While needing to add an xml subtree to an existing simplexml object, I noticed that simplexml_load_string fails with strings like

<emptynode></emptynode>



I needed to use dom instead of simplexml to bypass this problem and work with any kind of xml strings.

David Somerset
08-May-2007 08:39


Another option for having simplexml convert CDATA into plain text is to simply type cast the result to string. Here's an example:



$xmlRoot = simplexml_load_string('<?xml version="1.0"?>



<tvshows>

    <show>

        <name>The Simpsons</name>

    </show>

     <show>

        <name><![CDATA[Lois & Clark]]></name>

    </show>

</tvshows>');



$show = array();



foreach($xmlRoot as $val){

    $show[] = (string) $val->name;

    }

php at teamhirsch dot com
24-Apr-2007 11:46


It's worth noting that in the example above, $xml->body will actually return an object of type SimpleXMLElement, not a string, e.g. 



 SimpleXMLElement Object ( 

       [0] => this is the text in the body tag 

  )  



If you want to get a string out of it you must explicitly cast it using (string) or double quotes, or pass $xml->body (or whatever attribute you want to access) to any function that returns a string, such as urldecode() or trim().

m dot ament at mailcity dot com
06-Mar-2007 03:51


Warning:



The parsing of XML-data will stop when reaching character 0.

Please avoid this character in your XML-data.

mindpower
30-Jan-2007 12:03


A simple extension that adds a method for retrieving a specific attribute:



<?php

class simple_xml_extended extends SimpleXMLElement

{

    public    function    Attribute($name)

    {

        foreach($this->Attributes() as $key=>$val)

        {

            if($key == $name)

                return (string)$val;

        }

    }



}



$xml = simplexml_load_string('

<xml>

  <dog type="poodle" owner="Mrs Smith">Rover</dog>

</xml>', 'simple_xml_extended');



echo $xml->dog->Attribute('type');



?>



outputs 'poodle'



I prefer to use this technique rather than typecasting attributes.

h
15-Nov-2006 07:44


seems like simplexml has a line-length restriction - fails if a largeish XML doc with no linebreaks is passed as a string or file.



h

paul at santasoft dot com
25-Jul-2006 05:22


If you have PHP > 5.1 and LibXML > 2.6, use this function call to have simplexml convert CDATA into plain text.



simplexml_load_string($xmlstring, 'SimpleXMLElement', LIBXML_NOCDATA);



Too bad, so sad with PHP < 5.1.

add a note

WDDX

SimpleXML Functions