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
|
|