Is it possible to define a constant with variable name?

Question

I want to be able to generate some constants from an array. So something like this:

foreach ($array as $key => $value) {
    define($key,$value);
}

Is there a simple way to do this?

I see no need to use constants for this type of thing, why not just use the variables? — David, Feb 08 '13 at 19:44
look at http://stackoverflow.com/questions/12113663/dynamic-constants-in-php/12117642 — Vladimir Posvistelik, Feb 08 '13 at 19:53
It works fine. I just had something else in my code causing it not to work. Thanks for the help. — Jon Hester, Feb 08 '13 at 19:58

score 0 · Accepted Answer · answered Feb 08 '13 at 19:43

0

You're already doing this in your code. Or d you mean like this?

$array = array("sparkles" => "pretty");

foreach($array as $key=>$value) {
    ${$key} = $value;
}

echo $sparkles; //pretty

answered Feb 08 '13 at 19:43

Kermit

1

Those are variables, not constants – nice ass Feb 08 '13 at 19:46
It works as I wrote it. I haven't needed to do this before and there was another bug in another part of the code preventing it from working. I feel pretty stupid assuming it couldn't work as I wrote it, but appreciate all the help. – Jon Hester Feb 08 '13 at 19:57

nice ass · Answer 2 · 2013-02-08T20:08:16.297

0

An alternative, if you have many constants to define, and APC installed:

$constants = array(
    'ONE'   => 1,
    'TWO'   => 2,
    'THREE' => 3,
);
apc_define_constants('numbers', $constants);

(straight example from apc_define_constants)

edited Feb 08 '13 at 20:08

answered Feb 08 '13 at 19:51

nice ass

score 0 · Answer 3 · answered Feb 08 '13 at 19:52

0

Assuming PHP 5.3 or higher, you could do:

array_walk($array, function ($value, $key) { 
    define($key, $value);
});

or

array_walk(array_flip($array), 'define');

But honestly, I would just use your current method.

answered Feb 08 '13 at 19:52

Supericy

score -1 · Answer 4 · answered Feb 08 '13 at 19:48

-1

Also you can try to use extract function. It produces the same result (almost) as in njk's answer

answered Feb 08 '13 at 19:48

Oh, downvoting... Ok, it doesnt create any constants. To create constant in runtime you can try to use `eval` construction - but its a bad idea. Also you can look at my answer to the similar question: http://stackoverflow.com/questions/12113663/dynamic-constants-in-php/12117642#12117642 – Vladimir Posvistelik Feb 08 '13 at 19:52
What does eval have to do with creating a constant? – Supericy Feb 08 '13 at 19:57

4 Answers4