(PHP 5 >= 5.1.0)
SplObjectStorage::count — Returns the number of objects in the storage
Counts the number of objects in the storage.
此函数没有参数。
The number of objects in the storage.
Example #1 SplObjectStorage::count() example
<?php
$s = new SplObjectStorage();
$o1 = new StdClass;
$o2 = new StdClass;
$s->attach($o1);
$s->attach($o2);
$s->attach($o1);
var_dump($s->count());
var_dump(count($s));
?>
以上例程的输出类似于：
int(2) int(2)