摘要：<?php class Hubby{private function __construct() {}private function __clone() {}protected static $instance = null; public static function getInstance() { if (is_null(static::$instance)) { s

<?php 

class Hubby

{

private function __construct() {}

private function __clone() {}

protected static $instance = null;

public static function getInstance()

{

if (is_null(static::$instance)) {

static::$instance = new static();

}

return static::$instance;

}

}

$hubby1 = Hubby::getInstance();

$hubby2 = Hubby::getInstance();

echo ($hubby1 instanceof Hubby) ? '是' : '不是';

echo '<br>';

echo ($hubby2 instanceof Hubby) ? '是' : '不是';

echo '<br>';

echo ($hubby1 === $hubby2) ? '完全相等' : '不相等';

echo '<br>';

var_dump($hubby1, $hubby2);

批改老師：查無此人批改時間：2019-06-05 09:19:27
老師總結(jié)：完成的不錯，學(xué)習(xí)完類，就相當于php入門了。繼續(xù)加油。