OK, so maybe PHP's getElementById() is behaving according to spec, but it does not have the behaviour that people *want*...
Below is a global getElementById() function (i.e. not a DOMDocument method) which recursively searches through a document for a certain id value.
/* Find the first element in the document (sub)tree whose id attribute
has the value $id. By default, the entire document is searched - pass
a non-NULL value in $node to search only the subtree below $node. */
function getElementById(DOMDocument $doc, /*string*/ $id,
DOMNode $node = NULL) {
if ($node === NULL) return getElementById($doc, $id, $doc->documentElement);
$children = $node->childNodes;
for ($i = 0; $i < $children->length; ++$i) {
$elem = $children->item($i);
if (!($elem instanceof DOMElement)) continue;
if ($elem->getAttribute('id') == $id) return $elem;
$ret = getElementById($doc, $id, $elem);
if ($ret !== NULL) return $ret;
}
return NULL;
}
DOMDocument->getElementById()
(no version information, might be only in CVS)
DOMDocument->getElementById() -- Searches for an element with a certain id说明
class DOMDocument {DOMElement getElementById ( string elementId )
}
This function is similar to DOMDocument->getElementsByTagName() but searches for an element with a given id.
According to the DOM standard this requires a DTD which defines the attribute ID to be of type ID. You need to validate your document with DOMDocument->validate() or DOMDocument->validateOnParse before using this function.
范例
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User Contributed Notes
richard at 2006 dot atterer dot net
06-Jun-2006 03:51
06-Jun-2006 03:51
Tangui dot Le-Pense at laposte dot net
08-Apr-2006 09:00
08-Apr-2006 09:00
Validating a document from a DTD so as to use getElementById is sometimes impossible (for example when the head and body elements are not included yet in a XHtml document : the validation failed).
Fortunately, xml:id is supported by this function :)
That may be useful.
http://www.w3.org/TR/xml-id/
20-Dec-2005 11:04
If you're trying to use getElementById with a xml file validated on a xsd file you must first use the schemaValidate function or getElementById will return null
Example:
$dom = new DomDocument();
$dom->load("users.xml");
$dom->schemaValidate("users.xsd");
$curruser = $dom->getElementById($user->name);
bart at mediawave dot nl
11-Sep-2005 07:46
11-Sep-2005 07:46
It seems getElementById works fine without setting validateOnParse to true. Which is nice since setting this to true caused some performance problems with my script.
rafaeltovar at nodo50 dot org
04-Aug-2005 04:31
04-Aug-2005 04:31
Import a part to xml file to node of DOMDocument:
You have do put the correct DTD for ID attribute on XML file:
//----menu.xml----
<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE menu [
<!ELEMENT menu (item+)>
<!ATTLIST menu id ID #REQUIRED>
<!ELEMENT item (name, url)>
<!ELEMENT name (#PCDATA)>
<!ELEMENT url (#PCDATA)>
]>
<menu id="menu">
<item>
<name>item 1</name>
<url>item1.php</url>
</item>
<item>
<name>item 2</name>
<url>item2.php</url>
</item>
<item>
<name>item 3</name>
<url>item3.php</url>
</item>
<item>
<name>item 4</name>
<url>item4.php</url>
</item>
</menu>
//--------------------
<?
$dom = new DOMDocument('1.0', 'UTF-8');
$page = $dom->createElement('page');
$page = $dom->appendChild($page);
// Load a file
$domMenu = new DOMDocument();
$domMenu->validateOnParse = true;
$domMenu->load("xml/menu.xml");
// Use getElementById()
$element=$domMenu->getElementById("menu");
$menu = $dom->importNode($element, true);
$page->appendChild($menu);
?>
chregu at php dot net
02-Jul-2004 07:37
02-Jul-2004 07:37
http://wiki.bitflux.org/GetElementById_Pitfalls has an overview, of how to make getElementById work with aribtrary XML documents.