class_parents
This function can be used on traits as well as classes. Since traits 'use' other traits to create inheritance, this function allows you to get the parent trait(s) of another trait.
<?php
trait foo {
}
trait child {
use foo;
}
print_r(class_uses('child')); // Outputs array containing 'foo'
?>
class_uses
(PHP 5 >= 5.4.0)
class_uses — Return the traits used by the given class
Description
This function returns an array with the names of the traits that the
given class uses. This does however not include
any traits used by a parent class.
Parameters
-
class -
An object (class instance) or a string (class name).
-
autoload -
Whether to allow this function to load the class automatically through the __autoload() magic method.
Return Values
An array on success, or FALSE on error.
Examples
Example #1 class_uses() example
<?php
trait foo { }
class bar {
use foo;
}
print_r(class_uses(new bar));
print_r(class_uses('bar'));
function __autoload($class_name) {
require_once $class_name . '.php';
}
// use __autoload to load the 'not_loaded' class
print_r(class_uses('not_loaded', true));
?>
The above example will output something similar to:
Array
(
[foo] => foo
)
Array
(
[foo] => foo
)
Array
(
[trait_of_not_loaded] => trait_of_not_loaded
)
See Also
- class_parents() - Return the parent classes of the given class
- get_declared_traits() - Returns an array of all declared traits
add a note
User Contributed Notes
class_uses - [4 notes]
adam at adamhahn dot com ¶
7 hours ago
adam at adamhahn dot com ¶
1 day ago
FYI: It is not explicitly stated, but if you run this function against a class that does not use any traits it will return an empty array.
<?php
class iDontUseTraits {
}
class_uses('iDontUseTraits'); // Returns empty array
?>
benkuhl at gmail dot com ¶
4 months ago
[Edited by: googleguy at php dot net for clarity. It's obvious Xyz should have been Trait and not Class. ]
If your objective is to determine if a trait is being used by another class, you cannot use instanceOf...
<?php
Trait Xyz {
}
class Abc {
use Xyz;
}
$abc = new Abc();
var_dump($abc instanceOf Xyz); // false
?>
You must use this function with either an in_array or array_key_exists...
<?php
var_dump(array_key_exists('Xyz', class_uses($abc))); //true
?>
stealz at op dot pl ¶
5 months ago
To get ALL traits including those used by parent classes and other traits, use this function:
<?php
function class_uses_deep($class, $autoload = true) {
$traits = [];
do {
$traits = array_merge(class_uses($class, $autoload), $traits);
} while($class = get_parent_class($class));
foreach ($traits as $trait => $same) {
$traits = array_merge(class_uses($trait, $autoload), $traits);
}
return array_unique($traits);
}
?>