blocks|key|1193107|text|听起来使用单例方法比使用一堆静态方法更好|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1193108|class+Singleton
{
++/**
+++*+
+++*+@var+Singleton
+++*/
++private+static+$instance;

++private+function+__construct()
++{
++++//+Your+"heavy"+initialization+stuff+here
++}

++public+static+function+getInstance()
++{
++++if+(+is_null(+self::$instance+)+)
++++{
++++++self::$instance+=+new+self();
++++}
++++return+self::$instance;
++}

++public+function+someMethod1()
++{
++++//+whatever
++}

++public+function+someMethod2()
++{
++++//+whatever
++}
}|code-block|syntax|javascript|1193109|然后，在用法上|1193110|//+As+opposed+to+this
Singleton::someMethod1();

//+You'd+do+this
Singleton::getInstance()->someMethod1();|1193111|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Sounds like you'd be better served by a singleton rather than a bunch of static methods

<pre><code>class Singleton
{
 /**
 * 
 * @var Singleton
 */
 private static $instance;

 private function __construct()
 {
 // Your "heavy" initialization stuff here
 }

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

 public function someMethod1()
 {
 // whatever
 }

 public function someMethod2()
 {
 // whatever
 }
}
</code></pre>

And then, in usage

<pre><code>// As opposed to this
Singleton::someMethod1();

// You'd do this
Singleton::getInstance()-&gt;someMethod1();
</code></pre>

blocks|key|1193198|text|//+file+Foo.php
class+Foo
{
++static+function+init()+{+/*+...+*/+}
}

Foo::init();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1193199|这样，初始化就会在包含类文件时发生。通过使用自动加载，您可以确保这只在必要时发生(且只发生一次)。|unstyled|1193200|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>// file Foo.php
class Foo
{
 static function init() { /* ... */ }
}

Foo::init();
</code></pre>

This way, the initialization happens when the class file is included. You can make sure this only happens when necessary (and only once) by using autoloading.

blocks|key|978958|text|实际上，我在需要初始化(或者至少需要执行一些代码)的静态类上使用公共静态方法__init__()。然后，在我的自动加载器中，当它加载一个类时，它会检查is_callable($class,+'__init__')。如果是，它会调用该方法。快速，简单，有效...|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|978959|entityMap^0|12|A|23|V|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

Actually, I use a public static method <code>__init__()</code> on my static classes that require initialization (or at least need to execute some code). Then, in my autoloader, when it loads a class it checks <code>is_callable($class, '__init__')</code>. If it is, it calls that method. Quick, simple and effective...

blocks|key|978989|text|如果你不喜欢public静态初始化器，反射可以是一种变通办法。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|978990|<?php

class+LanguageUtility
{
++++public+static+function+initializeClass($class)
++++{
++++++++try
++++++++{
++++++++++++//+Get+a+static+method+named+'initialize'.+If+not+found,
++++++++++++//+ReflectionMethod()+will+throw+a+ReflectionException.
++++++++++++$ref+=+new+\ReflectionMethod($class,+'initialize');

++++++++++++//+The+'initialize'+method+is+probably+'private'.
++++++++++++//+Make+it+accessible+before+calling+'invoke'.
++++++++++++//+Note+that+'setAccessible'+is+not+available
++++++++++++//+before+PHP+version+5.3.2.
++++++++++++$ref->setAccessible(true);

++++++++++++//+Execute+the+'initialize'+method.
++++++++++++$ref->invoke(null);
++++++++}+++
++++++++catch+(Exception+$e)
++++++++{
++++++++}
++++}
}

class+MyClass
{
++++private+static+function+initialize()
++++{
++++}
}

LanguageUtility::initializeClass('MyClass');

?>|code-block|syntax|javascript|978991|entityMap^0|6|6|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

If you don't like <code>public</code> static initializer, reflection can be a workaround.

<pre class="lang-php prettyprint-override"><code>&lt;?php

class LanguageUtility
{
 public static function initializeClass($class)
 {
 try
 {
 // Get a static method named 'initialize'. If not found,
 // ReflectionMethod() will throw a ReflectionException.
 $ref = new \ReflectionMethod($class, 'initialize');

 // The 'initialize' method is probably 'private'.
 // Make it accessible before calling 'invoke'.
 // Note that 'setAccessible' is not available
 // before PHP version 5.3.2.
 $ref-&gt;setAccessible(true);

 // Execute the 'initialize' method.
 $ref-&gt;invoke(null);
 } 
 catch (Exception $e)
 {
 }
 }
}

class MyClass
{
 private static function initialize()
 {
 }
}

LanguageUtility::initializeClass('MyClass');

?&gt;
</code></pre>

blocks|key|1193269|text|有一种方法可以调用一次init()方法并禁止其使用，您可以将该函数转换为私有初始化器，并在类声明后调用它，如下所示：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1193270|class+Example+{
++++private+static+function+init()+{
++++++++//+do+whatever+needed+for+class+initialization
++++}
}
(static+function+()+{
++++static::init();
})->bindTo(null,+Example::class)();|code-block|syntax|javascript|1193271|entityMap^0|B|6|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

There is a way to call the <code>init()</code> method once and forbid it's usage, you can turn the function into private initializer and ivoke it after class declaration like this:

<pre><code>class Example {
 private static function init() {
 // do whatever needed for class initialization
 }
}
(static function () {
 static::init();
})-&gt;bindTo(null, Example::class)();
</code></pre>

I have an helper class with some static functions. All the functions in the class require a ‘heavy’ initialization function to run once (as if it were a constructor).

Is there a good practice for achieving this?

The only thing I thought of was calling an <code>init</code> function, and breaking its flow if it has already run once (using a static <code>$initialized</code> var). The problem is that I need to call it on every one of the class’s functions.

Static class initializer in PHP

我有一个带有一些静态函数的助手类。类中的所有函数都需要一个“重”初始化函数才能运行一次(就像它是一个构造函数一样)。有没有一个很好的实践来实现这个目标？我唯一想到的就是调用一个init函数，如果它已经运行过一次，就中断它的流(使用静态$initialized变量)。问题是我需要在类的每个函数上调用它。

问PHP中的静态类初始化器
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