ArrayObject
PHP Manual

ArrayObject::offsetExists

(PHP 5 >= 5.0.0)

ArrayObject::offsetExistsReturns whether the requested index exists

说明

bool ArrayObject::offsetExists ( mixed $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)


ArrayObject
PHP Manual