如何在 PHP 中创建单例? [英] How can I create a singleton in PHP?

问题描述

我在带有 PHP 5.3 的 Eclipse Indigo 上使用 PDT 和 Aptana，我想在类中创建一个单例.

I'm using PDT and Aptana on Eclipse Indigo with PHP 5.3 and I want to create a singleton in a class.

通过单例，我的意思是我只想拥有该对象的一个​​实例，并且其他对象或类通过返回该对象的函数获取该单个实例(因此这意味着我正在尝试创建一个对象在定义该对象的类中，即:在类 objA 中创建 objA)

By singleton, I mean I want to just have one instance of that object, and for other objects or classes to get that single instance via a function that returns that object (so this would mean I'm trying to create an object within the class that defines that object, ie: creating objA within the class objA)

我知道你不能只顾着去做:

I understand you can't just go a head and do this:

public $object = new Object();

在类定义中，你必须在构造函数中定义它.

with in a class definition, you have to define it in the constructor.

我该如何继续执行此操作?我来自 Java，所以可能是我混淆了一些基本的东西.任何帮助是极大的赞赏.代码如下:

How can I go ahead and do this? I'm coming from Java, so it could be I'm confusing some basic stuff. Any help is greatly appreciated. Here's the code:

<?php
  class Fetcher{

    private static $fetcher = new Fetcher(); //this is where I get the unexpected "new" error

    static function getFetcherInstance(){ 
      return $this->$fetcher;
    }
  }
?>

已解决！感谢大家的帮助！

推荐答案

试试这个:

<?php
class myclass{
    private static $_instance = null;

    public static function getInstance() {
        if (self::$_instance === null) {
            self::$_instance = new myclass();
        }

        return self::$_instance;
    }
}
?>

并调用它:

<?php
$obj = myclass::getInstace();
?>

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