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DOMDOCUMENT.GETELEMENTBYID(3) 1 DOMDOCUMENT.GETELEMENTBYID(3) DOMDocument::getElementById - Searches for an element with a certain id SYNOPSIS
public DOMElement DOMDocument::getElementById (string $elementId) DESCRIPTION
This function is similar to "DOMDocument::getElementsByTagName" but searches for an element with a given id. For this function to work, you will need either to set some ID attributes with "DOMElement::setIdAttribute" or a DTD which defines an attribute to be of type ID. In the later case, you will need to validate your document with "DOMDocument::validate" or DOMDocument::$vali- dateOnParse before using this function. PARAMETERS
o $elementId - The unique id value for an element. RETURN VALUES
Returns the DOMElement or NULL if the element is not found. EXAMPLES
Example #1 DOMDocument::getElementById() Example The following examples use book.xml which contains the following: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE books [ <!ELEMENT books (book+)> <!ELEMENT book (title, author+, xhtml:blurb?)> <!ELEMENT title (#PCDATA)> <!ELEMENT blurb (#PCDATA)> <!ELEMENT author (#PCDATA)> <!ATTLIST books xmlns CDATA #IMPLIED> <!ATTLIST books xmlns:xhtml CDATA #IMPLIED> <!ATTLIST book id ID #IMPLIED> <!ATTLIST author email CDATA #IMPLIED> ]> <?xml-stylesheet type="text/xsl" href="style.xsl"?> <books xmlns="http://books.php/" xmlns:xhtml="http://www.w3.org/1999/xhtml"> <book id="php-basics"> <title>PHP Basics</title> <author email="jim.smith@basics.php">Jim Smith</author> <author email="jane.smith@basics.php">Jane Smith</author> <xhtml:blurb><![CDATA[ <p><em>PHP Basics</em> provides an introduction to PHP.</p> ]]></xhtml:blurb> </book> <book id="php-advanced"> <title>PHP Advanced Programming</title> <author email="jon.doe@advanced.php">Jon Doe</author> </book> </books> <?php $doc = new DomDocument; // We need to validate our document before refering to the id $doc->validateOnParse = true; $doc->Load('book.xml'); echo "The element whose id is 'php-basics' is: " . $doc->getElementById('php-basics')->tagName . " "; ?> The above example will output: The element whose id is 'php-basics' is: book SEE ALSO
DOMDocument::getElementsByTagName. PHP Documentation Group DOMDOCUMENT.GETELEMENTBYID(3)
