(PHP 5 >= 5.1.0, PHP 7)
SplObjectStorage::contains — Checks if the storage contains a specific object
$object
) : boolChecks if the storage contains the object provided.
Returns TRUE if the object is in the storage, FALSE otherwise.
Example #1 SplObjectStorage::contains() example
<?php
$o1 = new StdClass;
$o2 = new StdClass;
$s = new SplObjectStorage();
$s[$o1] = "hello";
var_dump($s->contains($o1));
var_dump($s->contains($o2));
?>
以上例程的输出类似于：
bool(true) bool(false)