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关于单例模式的问题~

程序员文章站 2022-05-24 12:07:48
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name = $name;    }    public static function getInstance(){        if(self::$instance==null){            return new Singleton("");        }        return self::$instance;    }    public function printString(){        echo "hello,this is printString()"."
"; } public function setName($name){ $this->name = $name; } public function getName(){ echo "The name is ".$this->name."
"; }}$class = Singleton::getInstance();$class->printString();$class->setName("jack");$class->getName();$class2 = Singleton::getInstance();$class2->getName();


为何 $class2->getName() 输出的 name 也为空呢?


回复讨论(解决方案)

return new Singleton(""):
应为
self::$instance = new Singleton(""):

如果 return new Singleton(""): 的话就直接返回了另一个实例
就不是单例模式了

name = $name;    }    public static function getInstance(){        if(self::$instance==null){            return new Singleton("");        }        return self::$instance;    }    public function printString(){        echo "hello,this is printString()"."
"; } public function setName($name){ $this->name = $name; } public function getName(){ echo "The name is ".$this->name."
"; }}$class = Singleton::getInstance();$class->printString();$class->setName("jack");$class->getName();$class2 = Singleton::getInstance();$class2->getName();


为何 $class2->getName() 输出的 name 也为空呢?
谢谢楼上~

只要改一处代码即可:你忘了把单例放入$instance

    public static function getInstance(){        if(self::$instance==null){            self::$instance= new Singleton("");        }        return self::$instance;    }