Maison >développement back-end >tutoriel php >PHP里的单例类写法实例_PHP教程
这篇文章主要介绍了PHP里的单例类写法实例,本文直接给出代码实例,需要的朋友可以参考下
PHP里的单实例类在进行数据交换,节省内存上还是很有意义的。写个简单例子。
类1,单实例类本身:
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class UTIL { private static $instance; public function get() { if (!self::$instance) { self::$instance = new UTIL(); } return self::$instance; } public $number = 10; public function change($num) { $this->number += $num; } public function getNum() { return $this->number; } } |
类2,使用前述单实例类的应用类:
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class SINGLEA { private $numInst; function __construct() { $this->numInst = UTIL::get(); } public function change($num) { $this->numInst->change($num); } public function getNum() { return $this->numInst->getNum(); } } |
类3,同类2:
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class SINGLEB { private $numInst; function __construct() { $this->numInst = UTIL::get(); } public function change($num) { $this->numInst->change($num); } public function getNum() { return $this->numInst->getNum(); } } |
最后是调用的地方:
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$instA = new SINGLEA(); $instA->change(100); var_dump('SINGLEA CHANGED: '); var_dump($instA->getNum()); $instB = new SINGLEB(); $instB->change(-510); var_dump('SINGLEB CHANGED: '); var_dump($instB->getNum()); |
最后的显示结果:
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string'SINGLEA CHANGED: ' (length=17) int110 string'SINGLEB CHANGED: ' (length=17) int-400 |