DOMDocument->getElementById()

说明

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->validateOnParse before using this function.

参数

返回值

Returns the DOMElement or NULL if the element is not found.

范例

<?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 books is: " . $doc->getElementById('books')->tagName . "\n";

?>

The element whose id is books is: chapter

参见