If you are unable to upgrade to PHP 7.3 (not released at the time of writing), you can use this simple polyfill:
<?php
if (!function_exists('is_countable')) {
function is_countable($var) {
return (is_array($var) || $var instanceof Countable);
}
}
?>
is_countable
(PHP 7 >= 7.3.0, PHP 8)
is_countable — Verifica que el contenido de una variable es un valor contable
Descripción
Verifica que el contenido de una variable es un array o un objeto implementando Countable
Parámetros
-
var -
El valor a comprobar
Valores devueltos
Devuelve true si var es contable, false
en caso contrario.
Historial de cambios
| Versión | Descripción |
|---|---|
| 7.3.0 | is_countable() ha sido añadido. |
Ejemplos
Ejemplo #1 ejemplos de is_countable()
<?php
var_dump(is_countable([1, 2, 3])); // bool(true)
var_dump(is_countable(new ArrayIterator(['foo', 'bar', 'baz']))); // bool(true)
var_dump(is_countable(new ArrayIterator())); // bool(true)
var_dump(is_countable(new stdClass())); // bool(false)
Ver también
- is_array() - Comprueba si una variable es un array
- is_object() - Comprueba si una variable es un objeto
- is_iterable() - Verifica que el contenido de una variable es un valor iterable
- is_bool() - Comprueba si una variable es de tipo booleano
add a note
User Contributed Notes 6 notes
info at arisendrake dot de ¶
5 years ago
renic ¶
4 years ago
be wary of using is_object($var) and assuming that the object has implemented Countable. Not all objects are countable directly with count().
danmichaelo at gmail dot com ¶
5 years ago
Note that a polyfill for this method is also provided by the symfony/polyfill project.
Anonymous ¶
3 years ago
Fixed polyfill:
<?php
if (! function_exists('is_countable')) {
/**
* @param mixed $value The value to check
* @return bool
*/
function is_countable($value): bool
{
return is_array($value) || (is_object($value) && $value instanceof Countable);
}
}
?>
info at ensostudio dot ru ¶
3 years ago
Note: if is_countable() return true is does not guarantee that the it can be calculated recursively and correctly:
<?php
$iterator = new ArrayIterator(['one', 'two', new ArrayIterator(['three', 'four'])]);
var_dump(is_countable($iterator), count($iterator, COUNT_RECURSIVE));
// return TRUE and 3!
?>
deoomen ¶
5 years ago
Polyfill written by arisendrake is not quite good. It return FALSE when checking an Simple XML Node but count() works properly on PHP 7.1 and 7.3.
Better is this one:
<?php
if (version_compare(PHP_VERSION, "7.3") < 0 && !function_exists("is_countable")) {
function is_countable($var): bool
{
return (is_array($var) || is_object($var) || is_iterable($var) || $var instanceof Countable);
}
}
?>
