Calling static method from object array variable

Question

In PHP you can call a class's static method from an object instance (which is contained in an array) like this:

$myArray['instanceOfMyClass']::staticMethod(); // works

But for some reason when I use the $this variable, I get a parsing error. E.g:

$this->myArray['instanceOfMyClass']::staticMethod(); // PARSING ERROR

Just to illustrate what I mean:

class MyClass{
    public static function staticMethod(){ echo "staticMethod called\n"; }
}

$myArray = array();
$myArray['instanceOfMyClass'] = new MyClass;
$myArray['instanceOfMyClass']::staticMethod(); // works

class RunCode
{
    private $myArray;

    public function __construct(){
        $this->myArray = array();
        $this->myArray['instanceOfMyClass'] = new MyClass;
        $this->myArray['instanceOfMyClass']::staticMethod(); // PARSING ERROR
    }
}

new RunCode;

Any ideas on how to get around this?

Sorry? I don't think you get what I'm trying to do. I'm just trying to call a static method from an object instance of MyClass, which is an entry in RunCode->myArray. — Mark
– Mark, Commented Jul 17, 2012 at 9:19
use call_user_func(array($this->myArray['instanceOfMyClass'], 'staticMethod')); — Federkun
– Federkun, Commented Jul 17, 2012 at 10:01

Eugene · Accepted Answer · 2012-07-17 10:44:53Z

16

You actually can use "->" to call static method:

$this->myArray['instanceOfMyClass']->staticMethod();

answered Jul 17, 2012 at 10:44

Eugene

3,37524 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Mark Over a year ago

Oh wow, I never realised that thanks. So you can only use -> to call a static method if it's on an instantiated object?

Eugene Over a year ago

Yes. It seems quite safe since you can't add a non-static method with same name to the class.

helvete Over a year ago

Why does the PHP have to be this counter-intuitive? Anyway thanks fot the tip.

Sam Williams · Accepted Answer · 2012-07-17 10:05:53Z

6

This is a really interesting problem, it may even be a bug in PHP itself.

For a work around, use the KISS principle.

class RunCode
{
    private $myArray;

    public function __construct(){
        $this->myArray = array();
        $this->myArray['instanceOfMyClass'] = new MyClass;

        $instance = $this->myArray['instanceOfMyClass']
        $instance::staticMethod();
    }
}

Hope this helps!

answered Jul 17, 2012 at 10:05

Sam Williams

7351 gold badge6 silver badges15 bronze badges

1 Comment

Mark Over a year ago

Thanks, yeah I guess that is the most simple solution. My greatest pet peeve of PHP is the lack of support for syntax that you would just assume would work. E.g. $var = myFunction()[0]. Do you think this is worth filing a bug report about?

Rich · Accepted Answer · 2012-07-17 10:07:56Z

6

You will have to break up the one liner using a temporary variable, e.g.

$inst = $this->myArray['instanceOfMyClass'];
$inst::staticMethod()

This is one of many cases where PHP's compiler is not clever enough to understand nested expressions. The PHP devs have been improving this recently but there is still work to do.

answered Jul 17, 2012 at 10:07

Rich

15.5k3 gold badges73 silver badges126 bronze badges

Collectives™ on Stack Overflow

Calling static method from object array variable

3 Answers 3

3 Comments

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

3 Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related