ArrayObject::offsetExists
(PHP 5, PHP 7, PHP 8)
ArrayObject::offsetExists — Returns whether the requested index exists
说明
参数
-
key -
The index being checked.
返回值
true if the requested index exists, otherwise false
范例
示例 #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)
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User Contributed Notes 1 note
goran at extensionsforjoomla dot com ¶
14 years ago
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.
备份地址：http://www.lvesu.com/blog/php/arrayobject.offsetexists.php