If a new namespace is introduced while creating and inserting an attribute, createAttributeNS() does not behave in the same way as createElementNS().
(1) Location: With createAttributeNS(), the new namespace is declared at the level of the document element. By contrast, createElementNS() declares the new namespace at the level of the affected element itself.
(2) Timing: With createAttributeNS(), the new namespace is declared in the document as soon as the attribute is created - the attribute does not actually have to be inserted. createElementNS() doesn't affect the document as long as the element is not inserted.
An example:
<?php
$source = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<root><tag></tag></root>
XML;
/*
I. createAttributeNS:
* a new namespace shows up immediately, even without insertion of the attribute
* the new namespace is declared at the level of the document element
*/
$doc = new DOMDocument( '1.0' );
$doc->loadXML( $source );
// (1) We just create a "namespace'd" attribute without appending it to any element.
$attr_ns = $doc->createAttributeNS( '{namespace_uri_here}', 'example:attr' );
print $doc->saveXML() . "\n";
/*
Result: The namespace declaration appears, having been added to the document element. Output:
<?xml version="1.0" encoding="UTF-8"?>
<root xmlns:example="{namespace_uri_here}"><tag/></root>
*/
// (2) Next, we give the attribute a value and insert it.
$attr_ns->value = 'value';
$doc->getElementsByTagName( 'tag' )->item(0)->appendChild( $attr_ns );
print $doc->saveXML() . "\n";
/*
Result: The "namespace'd" attribute shows up as well. Output:
<?xml version="1.0" encoding="UTF-8"?>
<root xmlns:example="{namespace_uri_here}"><tag example:attr="value"/></root>
*/
/*
II. createElementNS:
* a new namespace shows up only when the element is inserted
* the new namespace is declared at the level of the inserted element
*/
$doc = new DOMDocument( '1.0' );
$doc->loadXML( $source );
// (1) We create a "namespace'd" element without inserting it into the document.
$elem_ns = $doc->createElementNS( '{namespace_uri_here}', 'example:newtag' );
print $doc->saveXML() . "\n";
/*
Result: The document remains unchanged. Output:
<?xml version="1.0" encoding="UTF-8"?>
<root><tag/></root>
*/
// (2) Next, we insert the new element.
$doc->getElementsByTagName( 'tag' )->item(0)->appendChild( $elem_ns );
print $doc->saveXML() . "\n";
/*
Result: The namespace declaration appears, and it is embedded in the element using it. Output:
<?xml version="1.0" encoding="UTF-8"?>
<root><tag><example:newtag xmlns:example="{namespace_uri_here}"/></tag></root>
*/
?>
DOMDocument::createAttributeNS
(PHP 5)
DOMDocument::createAttributeNS — Create new attribute node with an associated namespace
Description
This function creates a new instance of class DOMAttr. This node will not show up in the document unless it is inserted with (e.g.) DOMNode::appendChild().
Parameters
-
namespaceURI -
The URI of the namespace.
-
qualifiedName -
The tag name and prefix of the attribute, as prefix:tagname.
Return Values
The new DOMAttr or FALSE if an error occurred.
Errors/Exceptions
-
DOM_INVALID_CHARACTER_ERR -
Raised if
qualifiedNamecontains an invalid character. -
DOM_NAMESPACE_ERR -
Raised if
qualifiedNameis a malformed qualified name, or ifqualifiedNamehas a prefix andnamespaceURIisNULL.
See Also
- DOMNode::appendChild() - Adds new child at the end of the children
- DOMDocument::createAttribute() - Create new attribute
- DOMDocument::createCDATASection() - Create new cdata node
- DOMDocument::createComment() - Create new comment node
- DOMDocument::createDocumentFragment() - Create new document fragment
- DOMDocument::createElement() - Create new element node
- DOMDocument::createElementNS() - Create new element node with an associated namespace
- DOMDocument::createEntityReference() - Create new entity reference node
- DOMDocument::createProcessingInstruction() - Creates new PI node
- DOMDocument::createTextNode() - Create new text node
_ michael ¶
2 years ago
