(PHP 5 >= 5.1.0, PHP 7, PHP 8)
SplObjectStorage::attach — Adds an object in the storage
Adds an object inside the storage, and optionally associate it to some data.
没有返回值。
示例 #1 SplObjectStorage::attach() example
<?php
$o1 = new stdClass;
$o2 = new stdClass;
$s = new SplObjectStorage();
$s->attach($o1); // similar to $s[$o1] = NULL;
$s->attach($o2, "hello"); // similar to $s[$o2] = "hello";
var_dump($s[$o1]);
var_dump($s[$o2]);
?>以上示例的输出类似于：
NULL string(5) "hello"