PHP 手册
后退		前进

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.

参数

elementId: The unique id value for an element.

返回值

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

范例

例子 1. DOMDocument->getElementById() Example


<?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";

?>

上例将输出：

The element whose id is books is: chapter

参见

DOMDocument->getElementsByTagName()

后退	起点	前进
DOMDocument->createTextNode()	上一级	DOMDocument->getElementsByTagName()