6

Is it possible to test if a variable is static in PHP? I am trying create a magic method __get that also looks at static variables. I find that property_exists() returns true when a variable is static too. But I will need to use :: instead of -> I'd expect?

hakre
  • 193,403
  • 52
  • 435
  • 836
JM at Work
  • 2,417
  • 7
  • 33
  • 46

2 Answers2

7

It is possible to test if a variable is static via Reflection: 

class Foo { static $bar; }
$prop = new ReflectionProperty('Foo', 'bar');
var_dump($prop->isStatic()); // TRUE

However, that still won't allow you to use them with magic methods __get or __set, because those only work in object context. From the PHP Manual on Magic Methods:

Property overloading only works in object context. These magic methods will not be triggered in static context. Therefore these methods should not be declared static. As of PHP 5.3.0, a warning is issued if one of the magic overloading methods is declared static.

Also see this discussion on the PHP Internals Mailing List about introducing __getStatic:

Gordon
  • 312,688
  • 75
  • 539
  • 559
  • I managed to do it with something like `return static::$$prop` :) or is there something wrong with that? – JM at Work Jul 04 '11 at 09:08
  • @JM having to use late static binding and variable variables are not exactly indicators of good design. [Statics are death to testability](http://sebastian-bergmann.de/archives/883-Stubbing-and-Mocking-Static-Methods.html) and [considered harmful](http://kore-nordmann.de/blog/0103_static_considered_harmful.html) – Gordon Jul 04 '11 at 09:14
0

I don't think you can access undeclared static property using magic __get() method. It will raise PHP Fatal error. At least with PHP of version 5.3.

That's the result if you will try to access the property as static ClassName::$propertyName of course.

Gedrox
  • 3,592
  • 1
  • 21
  • 29