没有实例的类 [英] Classes without instances

问题描述

在很多情况下，脚本中只需要一个类的单个实例。

因为PHP5提供了像MyClass这样的类变量： ：$ myVar甚至类

常量，在我看来不需要实例化。是的，因为没有实例化，使用一个类是好的和良好做法吗？在

这种情况​​下，我可以将这样的类视为函数集合和

变量，它们在某种程度上属于一起，并且前缀类名称可以是

作为一种命名空间标识符：


包含myLib.php

myLib :: $ somevar =''some value'';

myLib :: somefunc（myLib :: MY_CONSTANT）;


另一个问题：在PHP4中我可以有


class myLib {function myFunc（）{/ * do stuff * /}}

myLib :: myFunc（）;


在PHP5中，有"静"关键词。究竟有什么区别



class myLib {public static function myFunc（）{/ * do stuff * /}}

class myLib {public function myFunc（）{/ * do stuff * /}}

问候，

Thomas

解决方案

myVar甚至类

常量，在我看来不需要实例化。是的，因为没有实例化，使用一个类是好的和良好做法吗？在

这种情况​​下，我可以将这样的类视为函数集合和

变量，它们在某种程度上属于一起，并且前缀类名称可以是

作为一种命名空间标识符：


包含myLib.php

myLib ::

somevar =''some value'';

myLib :: somefunc（myLib :: MY_CONSTANT）;


另一个问题：在PHP4中我可以拥有


class myLib {function myFunc（）{/ * do stuff * /}}

myLib :: myFunc（）;


在PHP5中，有静态和静态。关键词。究竟有什么区别



class myLib {public static function myFunc（）{/ * do stuff * /}}

class myLib {public function myFunc（）{/ * do stuff * /}}

问候，

Thomas

>在PHP5中，存在静态和静态。关键词。

类myLib {public static function myFunc（）{/ * do stuff * /}}
class myLib {public function myFunc - 究竟有什么区别

（）{/ *做东西* /}}

在第一种情况下，函数myFunc（）将在没有

实例化的情况下可用。

然后你可以打电话给

myLib :: myFunc（）

第二种情况你不能


在PHP 4中没关系，你可以随时（？）调用一个函数

静态

这可能导致奇怪的结果（可能使用的函数）一个变量

尚未初始化。

现在在PHP 5中我们有静态


Mei？o

Hi,

In many cases, one needs only a single instance of a class in a script.
Since PHP5 offers class variables like MyClass::$myVar and even class
constants, it seems to me that an instantiation is not needed. Is it
therefore okay and good practise to use a class without instantiation? In
that case I could regard such a class as a collection of functions and
variables that belong together in a way and the prefixed class name could
serve as a kind of namespace identifier:

include "myLib.php"
myLib::$somevar = ''some value'';
myLib::somefunc( myLib::MY_CONSTANT );

Another question: In PHP4 I can have

class myLib { function myFunc() { /* do stuff */ } }
myLib::myFunc();

In PHP5, there is the "static" keyword. What exactly is the difference
between

class myLib { public static function myFunc() { /* do stuff */ } }
class myLib { public function myFunc() { /* do stuff */ } }

Greetings,
Thomas

解决方案

myVar and even class
constants, it seems to me that an instantiation is not needed. Is it
therefore okay and good practise to use a class without instantiation? In
that case I could regard such a class as a collection of functions and
variables that belong together in a way and the prefixed class name could
serve as a kind of namespace identifier:

include "myLib.php"
myLib::

somevar = ''some value'';
myLib::somefunc( myLib::MY_CONSTANT );

Another question: In PHP4 I can have

class myLib { function myFunc() { /* do stuff */ } }
myLib::myFunc();

In PHP5, there is the "static" keyword. What exactly is the difference
between

class myLib { public static function myFunc() { /* do stuff */ } }
class myLib { public function myFunc() { /* do stuff */ } }

Greetings,
Thomas

> In PHP5, there is the "static" keyword. What exactly is the difference

between

class myLib { public static function myFunc() { /* do stuff */ } }
class myLib { public function myFunc() { /* do stuff */ } }

in this first case the function myFunc() will be available without
instantiation.
then you can call
myLib::myFunc()
second case you can''t

In PHP 4 it didn''t matter, you could always (?) call a function
staticly
which may lead to strange results (maybe the function used a variable
which hasn''t been initialized).
Now in PHP 5 we have static

Mei?o

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