DOMDocument->getElementById()

(No version information available, might be only in CVS)

DOMDocument->getElementById() — Searches for an element with a certain id

说明

DOMDocument

DOMElement getElementById ( string $elementId )

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

elementId: The unique id value for an element.

返回值

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

范例

Example#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()


	PHP5中文手册 DOMDocument->createTextNode() DOMDocument->getElementsByTagName() DOM PHP Manual DOMDocument->getElementById() (No version information available, might be only in CVS) DOMDocument->getElementById() — Searches for an element with a certain id 说明 DOMDocument DOMElement getElementById ( string `$elementId` ) 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 `elementId` The unique id value for an element. 返回值 Returns the DOMElement or `NULL` if the element is not found. 范例 Example#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() DOMDocument->createTextNode() DOMDocument->getElementsByTagName() DOM PHP Manual