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PHP - Manual: dom_import_simplexml

2024-11-14

dom_import_simplexml

(PHP 5, PHP 7, PHP 8)

dom_import_simplexml Gets a DOMElement object from a SimpleXMLElement object

说明

dom_import_simplexml(object $node): DOMElement

This function takes the node node of class SimpleXML and makes it into a DOMElement node. This new object can then be used as a native DOMElement node.

参数

node

The SimpleXMLElement node.

返回值

The DOMElement node added.

更新日志

版本 说明
8.0.0 This function no longer returns null on failure.

范例

示例 #1 Import SimpleXML into DOM with dom_import_simplexml()

<?php

$sxe 
simplexml_load_string('<books><book><title>blah</title></book></books>');

if (
$sxe === false) {
    echo 
'Error while parsing the document';
    exit;
}

$dom_sxe dom_import_simplexml($sxe);
if (!
$dom_sxe) {
    echo 
'Error while converting XML';
    exit;
}

$dom = new DOMDocument('1.0');
$dom_sxe $dom->importNode($dom_sxetrue);
$dom_sxe $dom->appendChild($dom_sxe);

echo 
$dom->saveXML();

?>

参见

add a noteadd a note

User Contributed Notes 5 notes

up
14
crescentfreshpot at yahoo dot com
14 years ago
justinpatrin at php dot net:
> To get a proper DOM document (which you need to do most things) you need...

No you don't. Just do:
<?php
$dom
= dom_import_simplexml($xml)->ownerDocument;
?>
up
3
h4ss4n3 at hyj4z1 dot me
1 year ago
//No need to initiate, import and append on example#1

(...)
$dom_sxe = dom_import_simplexml($sxe);
if (!$dom_sxe) {
    echo 'Erreur lors de la conversion du XML';
    exit;
}

//$dom = new DOMDocument('1.0');
//$dom_sxe = $dom->importNode($dom_sxe, true);
//$dom_sxe = $dom->appendChild($dom_sxe);

//use ownerDocument propertie
echo $dom->ownerDocument->saveXML();

?>
up
9
Jeff M
13 years ago
SimpleXML is an 'Object Mapping XML API'. It is not DOM, per se. SimpleXML converts the XML elements into PHP's native data types.

The dom_import_simplexml and simplexml_import_dom functions do *not* create separate copies of the original object. You are free to use the methods of either or both interchangeably, since the underlying instance is the same.

<?php
   
// initialize a simplexml object
   
$sxe = simplexml_load_string('<root/>');
   
   
// get a dom interface on the simplexml object
   
$dom = dom_import_simplexml($sxe);

   
// dom adds a new element under the root
   
$element = $dom->appendChild(new DOMElement('dom_element'));
   
   
// dom adds an attribute on the new element
   
$element->setAttribute('creator', 'dom');

   
// simplexml adds an attribute on the dom element
   
$sxe->dom_element['sxe_attribute'] = 'added by simplexml';

   
// simplexml adds a new element under the root
   
$element = $sxe->addChild('sxe_element');
   
   
// simplexml adds an attribute on the new element
   
$element['creator'] = 'simplexml';

   
// dom finds the simplexml element (via DOMNodeList->index)
   
$element = $dom->getElementsByTagName('sxe_element')->item(0);

   
// dom adds an attribute on the simplexml element
   
$element->setAttribute('dom_attribute', 'added by dom');
   
    echo (
'<pre>');           
   
print_r($sxe);
    echo (
'</pre>');
?>

Outputs:

SimpleXMLElement Object
(
    [dom_element] => SimpleXMLElement Object
        (
            [@attributes] => Array
                (
                    [creator] => dom
                    [sxe_attribute] => added by simplexml
                )

        )

    [sxe_element] => SimpleXMLElement Object
        (
            [@attributes] => Array
                (
                    [creator] => simplexml
                    [dom_attribute] => added by dom
                )

        )

)

What this illustrates is that both interfaces are operating on the same underlying object instance. Also, when you dom_import_simplexml, you can create and add new elements without reference to an ownerDocument (or documentElement).

So passing a SimpleXMLElement to another method does not mean the recipient is limited to using SimpleXML methods.

Hey Presto! Your telescope has become a pair of binoculars!
up
1
justinpatrin at php dot net
16 years ago
I've found that newer versions of PHP5 require some special syntax in order to properly convert between SimpleXML and DOM. It's not as easy as calling dom_import_simplexml() with a SimpleXML node. To get a proper DOM document (which you need to do most things) you need:
<?php
//$xml is a SimpleXML instance
$domnode = dom_import_simplexml($xml);
$dom = new DOMDocument();
$domnode = $dom->importNode($domnode, true);
$dom->appendChild($domnode);
?>

Switching back, though, is, well...simple.

<?php
//$dom is a DOMDocument instance
$xml = simplexml_import_dom($dom);
?>
up
0
biniou at yopmail dot com
6 years ago
Very useful to add a CDATA node with SimpleXMLElement (use it like addChild) :

<?php
class My_SimpleXMLElement extends SimpleXMLElement {
   
    public function
addChildWithCData($name, $value = NULL) {
       
$new_child = $this->addChild($name);
       
       
$node = dom_import_simplexml($new_child);
       
$no = $node->ownerDocument;
       
$node->appendChild($no->createCDATASection($value));
   
        return
$new_child;
    }
}

官方地址:https://www.php.net/manual/en/function.dom-import-simplexml.php

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