PHP单例模式

 1 <?php
 2 /**
 3  * Single.php
 4  * Created on 2019/8/30 10:03
 5  * Created by Wilin
 6  */
 7 
 8 class Single
 9 {
10     private static $instance;
11 
12     //防止直接创建对象
13     private function __construct(){}
14     //防止克隆
15     private function __clone(){}
16 
17     public static function getInstance(){
18         if (!self::$instance instanceof self) {
19             self::$instance = new self();
20         }
21         return self::$instance;
22     }
23 }