get_defined_constants

    (PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)

    get_defined_constants — Devuelve un array asociativo con los nombres de todas las constantes y sus valores

    Descripción

    function get_defined_constants(bool $categorize = false): array

    Devuelve los nombres y valores de todas las constantes definidas actualmente. Esto incluye las constantes definidas por las extensiones y aquellas creadas con la función define(). Sin embargo, excluye las constantes mágicas, que se resuelven en tiempo de compilación.

    Parámetros

    categorize

    Permite a esta función devolver un array multidimensional con las categorías como claves de la primera dimensión y las constantes junto con sus valores en la segunda dimensión. 

    <?php
define("MY_CONSTANT", 1);
print_r(get_defined_constants(true));
?>

    Resultado del ejemplo anterior es similar a:

    Array
(
    [Core] => Array
        (
            [E_ERROR] => 1
            [E_WARNING] => 2
            [E_PARSE] => 4
            [E_NOTICE] => 8
            [E_CORE_ERROR] => 16
            [E_CORE_WARNING] => 32
            [E_COMPILE_ERROR] => 64
            [E_COMPILE_WARNING] => 128
            [E_USER_ERROR] => 256
            [E_USER_WARNING] => 512
            [E_USER_NOTICE] => 1024
            [E_ALL] => 30719
            [TRUE] => 1
        )

    [pcre] => Array
        (
            [PREG_PATTERN_ORDER] => 1
            [PREG_SET_ORDER] => 2
            [PREG_OFFSET_CAPTURE] => 256
            [PREG_SPLIT_NO_EMPTY] => 1
            [PREG_SPLIT_DELIM_CAPTURE] => 2
            [PREG_SPLIT_OFFSET_CAPTURE] => 4
            [PREG_GREP_INVERT] => 1
        )

    [user] => Array
        (
            [MY_CONSTANT] => 1
        )

)

    Valores devueltos

    Devuelve un array de constantes en el formato "nombre de la constante" => "valor de la constante", opcionalmente agrupadas por el nombre de la extensión que registró la constante.

    Ejemplos

    Ejemplo #1 Ejemplo con get_defined_constants()

    <?php
print_r(get_defined_constants());
?>

    Resultado del ejemplo anterior es similar a:

    Array
(
    [E_ERROR] => 1
    [E_WARNING] => 2
    [E_PARSE] => 4
    [E_NOTICE] => 8
    [E_CORE_ERROR] => 16
    [E_CORE_WARNING] => 32
    [E_COMPILE_ERROR] => 64
    [E_COMPILE_WARNING] => 128
    [E_USER_ERROR] => 256
    [E_USER_WARNING] => 512
    [E_USER_NOTICE] => 1024
    [E_ALL] => 30719
    [TRUE] => 1
)

    Véase también

    Found A Problem?

    Learn How To Improve This Page • Submit a Pull Request • Report a Bug
    ＋add a note

    User Contributed Notes 5 notes

    up
    24
    Bob
    18 years ago
    Add this method to your class definition if you want an array of class constants (get_defined_constants doesn't work with class constants as Peter P said above):

<?php
public function get_class_constants()
{
    $reflect = new ReflectionClass(get_class($this));
    return $reflect->getConstants());
}
?>

You could also override stdObject with it so that all your classes  have this method
    up
    13
    R4FC0R3
    8 years ago
    If you want to access directly on one category, just use:

<?php

print_r(get_defined_constants(true)['Core']);

?>

you can replace 'Core' by the category you wish (e.g. user):

<?php

print_r(get_defined_constants(true)['user']);

?>

Warning: only use this on development side
    up
    9
    Anonymous
    20 years ago
    If you want to filter through and return only the prefix for your constants (i.e. you have constants with a naming scheme), then you can use this quick little function. It comes in handy for debugging.

<?php
function returnConstants ($prefix) {
    foreach (get_defined_constants() as $key=>$value) 
        if (substr($key,0,strlen($prefix))==$prefix)  $dump[$key] = $value; 
    if(empty($dump)) { return "Error: No Constants found with prefix '".$prefix."'"; }
    else { return $dump; }
}
?>

Example:

<?php
define("SITENAME_OPTION_ONE",true);
define("SITENAME_OPTION_TWO",false);
define("SITENAME_URL","foo");

print_r(returnConstants("SITENAME_OPTION"));
?>

Will return:

Array
(
    [SITENAME_OPTIONONE] => 1
    [SITENAME_OPTIONTWO] => 
)
    up
    5
    me at gogogadgetscott dot info
    21 years ago
    <?php
/**
 * Convert constant value into string name.
 *
 * @param  mixed  Constant value.
 * @return string Constant name.
 * @access public
 */
function sch_get_consant($value)
{
    $constants = get_defined_constants();
    $name = array_search($value, $constants, TRUE);    
    return $name;
}
?>
    up
    -4
    S-Tian
    4 years ago
    If you want to create a static method that you can copy and paste into each class you have constants created, you can use:

<php
public static function get_class_constants(): array
{
    $reflect = new ReflectionClass(self::class);

    return $reflect->getConstants();
}
?>
    ＋add a note
    To Top