Can I get CONST's defined on a PHP class?

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I have several CONST's defined on some classes, and want to get a list of them. For example:

class Profile {
    const LABEL_FIRST_NAME = "First Name";
    const LABEL_LAST_NAME = "Last Name";
    const LABEL_COMPANY_NAME = "Company";
}

Is there any way to get a list of the CONST's defined on the Profile class? As far as I can tell, the closest option(get_defined_constants()) won't do the trick.

What I actually need is a list of the constant names - something like this:

array('LABEL_FIRST_NAME',
    'LABEL_LAST_NAME',
    'LABEL_COMPANY_NAME')

Or:

array('Profile::LABEL_FIRST_NAME', 
    'Profile::LABEL_LAST_NAME',
    'Profile::LABEL_COMPANY_NAME')

Or even:

array('Profile::LABEL_FIRST_NAME'=>'First Name', 
    'Profile::LABEL_LAST_NAME'=>'Last Name',
    'Profile::LABEL_COMPANY_NAME'=>'Company')
12 Answers

You can use Reflection for this. Note that if you are doing this a lot you may want to looking at caching the result.

<?php
class Profile {
    const LABEL_FIRST_NAME = "First Name";
    const LABEL_LAST_NAME = "Last Name";
    const LABEL_COMPANY_NAME = "Company";
}


$refl = new ReflectionClass('Profile');
print_r($refl->getConstants());

Output:

Array
(
    'LABEL_FIRST_NAME' => 'First Name',
    'LABEL_LAST_NAME' => 'Last Name',
    'LABEL_COMPANY_NAME' => 'Company'
)

Use token_get_all(). Namely:

<?php
header('Content-Type: text/plain');

$file = file_get_contents('Profile.php');
$tokens = token_get_all($file);

$const = false;
$name = '';
$constants = array();
foreach ($tokens as $token) {
    if (is_array($token)) {
        if ($token[0] != T_WHITESPACE) {
            if ($token[0] == T_CONST && $token[1] == 'const') {
                $const = true;
                $name = '';
            } else if ($token[0] == T_STRING && $const) {
                $const = false;
                $name = $token[1];
            } else if ($token[0] == T_CONSTANT_ENCAPSED_STRING && $name) {
                $constants[$name] = $token[1];
                $name = '';
            }
        }
    } else if ($token != '=') {
        $const = false;
        $name = '';
    }
}

foreach ($constants as $constant => $value) {
    echo "$constant = $value\n";
}
?>

Output:

LABEL_FIRST_NAME = "First Name"
LABEL_LAST_NAME = "Last Name"
LABEL_COMPANY_NAME = "Company"

In PHP5 you can use Reflection: (manual reference)

$class = new ReflectionClass('Profile');
$consts = $class->getConstants();

Yeah, you use reflection. Look at the output of

<?
Reflection::export(new ReflectionClass('YourClass'));
?>

That should give you the idea of what you'll be looking at.

class Qwerty 
{
    const __COOKIE_LANG_NAME__ = "zxc";
    const __UPDATE_COOKIE__ = 30000;

    // [1]
    public function getConstants_(){

        return ['__COOKIE_LANG_NAME__' => self::__COOKIE_LANG_NAME__, 
                '__UPDATE_COOKIE__' => self::__UPDATE_COOKIE__]; 
    }    

    // [2]
    static function getConstantsStatic_(){

        return ['__COOKIE_LANG_NAME__' => self::__COOKIE_LANG_NAME__, 
                '__UPDATE_COOKIE__' => self::__UPDATE_COOKIE__]; 
    } 
}

// [1]
$objC = new Qwerty();
var_dump($objC->getConstants_());

// [2]
var_dump(Qwerty::getConstantsStatic_());
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