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ArrayObject::offsetExists

(PHP 5, PHP 7, PHP 8)

ArrayObject::offsetExists — Returns whether the requested index exists

说明

public ArrayObject::offsetExists(mixed $key): bool

参数

key: The index being checked.

返回值

true if the requested index exists, otherwise false

示例

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'));
?>

以上示例会输出：

bool(true)
bool(true)
bool(false)