php设计模式之单例模式的例子，供大家参考，具体内容如下
rndId = rand();
}
public function whatAmI(){
echo 'I am a Apple(' . $this->rndId . ')
';
}
public static function getInstance(){
//echo get_class();
return Fruit::getSingleton(get_class());
}
}
class GreenApple extends Apple{
public function whatAmI(){
echo 'I am a GreenApple(' . $this->rndId . ')
';
}
public static function getInstance(){
return Fruit::getSingleton(get_class());
}
}
$apple1 = Apple::getInstance();
//var_dump($apple1);
$apple2 = GreenApple::getInstance();
$apple1->whatAmI();// should echo 'I am a Apple(some number)
$apple2->whatAmI();// should echo 'I am a GreenApple(some number)
$apple1 = Apple::getInstance();
$apple2 = GreenApple::getInstance();
//保证单例模式
$apple1->whatAmI();// should echo 'I am a Apple(same number as above)
$apple2->whatAmI();// should echo 'I am a GreenApple(same number as above)
// $a = clone $apple1;// this should fail
// $b = clone $apple2;// this should fail
以上就是本文的全部内容，希望对大家学习php程序设计有所帮助。