ArrayObject::offsetExists
(PHP 5 >= 5.0.0)
ArrayObject::offsetExists — Returns whether the requested index exists
说明
$index
)参数
-
index -
The index being checked.
返回值
TRUE if the requested index exists, otherwise FALSE
范例
Example #1 ArrayObject::offsetExists() example
<?php
$arrayobj = new ArrayObject (array( 'zero' , 'one' , 'example' => 'e.g.' ));
var_dump ( $arrayobj -> offsetExists ( 1 ));
var_dump ( $arrayobj -> offsetExists ( 'example' ));
var_dump ( $arrayobj -> offsetExists ( 'notfound' ));
?> 以上例程会输出：
bool(true) bool(true) bool(false)
用户评论:
[#1] goran at extensionsforjoomla dot com [2007-07-09 03:52:35]
In versions prior to PHP 5.2.2 offsetExists() would return false if index value is null.
<?php
// running PHP 5.2.1
$params = new ArrayObject(array('INT'=>null, 'STR'=> null, 'BOOL'=>null, 'LOB'=>null));
$test = $params->offsetExists('INT');
var_dump($test);
// result would be bool(false)
// running PHP 5.2.2
$params = new ArrayObject(array('INT'=>null, 'STR'=> null, 'BOOL'=>null, 'LOB'=>null));
$test = $params->offsetExists('INT');
var_dump($test);
// result would be bool(true)
?>
Both tests where made on Windows platform.