(PHP 5, PHP 7, PHP 8)
DOMNode::insertBefore — Añade un nuevo hijo antes del nodo de referencia
Esta función inserta un nuevo nodo justo antes que el nodo de referencia. Si planea hacer modificaciones posteriores al hijo añadido debe usar el nodo devuelto.
newnodeEl nuevo nodo.
refnode
El nodo de referencia. Si no se proporciona, newnode es
añadido al hijo.
El nodo insertado.
DOM_NO_MODIFICATION_ALLOWED_ERRLanzado si este nodo es de sólo lectura o si el padre previo del nodo que va a ser insertado es de sólo lectura.
DOM_HIERARCHY_REQUEST_ERR
Lanzado si este nodo es de un tipo de no permite hijos del tipo
del nodo newnode, o si el nodo a
añadir es uno de los progenitores del nodo o si es el nodo en sí.
DOM_WRONG_DOCUMENT_ERR
Lanzado si newnode fue creado desde un documento
diferente del que creó este nodo.
DOM_NOT_FOUND
Lanzado si refnode no es un hijo de este nodo.
1st argument) a node to insert
2nd argument) a reference node - this is the node that the new node will be inserted before
The trick to using this method is that the OBJECT on which you actually CALL the insertBefore() method is actually the PARENT node of the reference node!
INCORRECT:
$DOMNode_refNode->insertBefore($DOMNode_newNode, $DOMNode_refNode);
CORRECT:
$DOMNode_refNode->parentNode->insertBefore($DOMNode_newNode, $DOMNode_refNode);Note that supplying the same node for $newnode and $refnode leads to an E_WARNING ("Couldn't add newnode as the previous sibling of refnode"). For example imagine one wanted to make $newnode the first child of its parent by doing:
<?php
$firstSibling = $newnode->parentNode->firstChild;
// Bad:
$newnode->parentNode->insertBefore( $newnode, $firstSibling );
?>
This would generate a warning if it already was the first child of its parent, since $newnode and $firstSibling are identical. Easy to work around though:
<?php
$firstSibling = $newnode->parentNode->firstChild;
// Better:
if( $newnode !== $firstSibling ) {
$newnode->parentNode->insertBefore( $newnode, $firstSibling );
}
?>example to insert <newnode/> between <chid1/> and <child2/>
<?xml version="1.0" encoding="ISO-8859-1" ?>
<root>
<parent>
<child nr="1"/>
<child nr="2"/>
</parent>
</root>
<?php
$xml_src = 'test.xml';
// XPath-Querys
$parent_path = "//parent";
$next_path = "//parent/child[@nr='2']";
// Create a new DOM document
$dom = new DomDocument();
$dom->load($xml_src);
// Find the parent node
$xpath = new DomXPath($dom);
// Find parent node
$parent = $xpath->query($parent_path);
// new node will be inserted before this node
$next = $xpath->query($next_path);
// Create the new element
$element = $dom->createElement('newnode');
// Insert the new element
$parent->item(0)->insertBefore($element, $next->item(0));
echo $dom->saveXML();
?>Sorry, my previous posting worked only for the top node. Here the corrected version, which will work for any node:
XML
----
<?xml version="1.0"?>
<contacts>
<person>Adam</person>
<person>Eva</person>
<person>Thomas</person>
</contacts>
PHP
---
<?php
// load XML, create XPath object
$xml = new DomDocument();
$xml->preserveWhitespace = false;
$xml->load('contacts.xml');
$xpath = new DOMXPath($xml);
// get node eva, which we will append to
$eva = $xpath->query('/contacts/person[.="Eva"]')->item(0);
// create node john
$john = $xml->createElement('person', 'John');
// insert john after eva
// "in eva's parent node (=contacts) insert
// john before eva's next node"
// this also works if eva would be the last node
$eva->parentNode->insertBefore($john, $eva->nextSibling);
// show result
header('Content-Type: text/plain');
print $xml->saveXML();
?>
Result
------
<?xml version="1.0"?>
<contacts>
<person>Adam</person>
<person>Eva</person><person>John</person>
<person>Thomas</person>
</contacts>The previous example is incorrect, and causes a DOM_NOT_FOUND error, as the child nodes are not direct descendants of the root node.
Therefore, the line:
$parent_path = "/root";
needs to change to:
$parent_path = "/root/parent";
or
$parent_path = "//parent";
for this example to work