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get_parent_class

(PHP 4, PHP 5, PHP 7, PHP 8)

get_parent_classObtém o nome da classe pai para o objeto ou classe

Descrição

get_parent_class(object|string $object_or_class = ?): string|false

Obtém o nome da classe pai para o objeto ou classe.

Parâmetros

object_or_class

O objeto testado ou o nome da classe.

Valor Retornado

Retorna o nome da classe pai da classe da qual object_or_class é uma instância ou o nome.

Se o objeto não tiver um pai ou a classe informada não existir, será retornado false.

Registro de Alterações

Versão Descrição
8.3.0 Chamar get_parent_class() sem um argumento agora emite um alerta E_DEPRECATED; anteriormente, chamar esta função de dentro de uma classe retornava o nome dessa classe.
8.0.0 O parâmetro object_or_class agora aceita apenas objetos ou nomes de classe válidos.

Exemplos

Exemplo #1 Usando get_parent_class()

<?php

class Pai {
function
__construct()
{
// implemente alguma lógica
}
}

class
Filha extends Pai {
function
__construct()
{
echo
"Eu sou filha de " , get_parent_class($this) , "\n";
}
}

class
Filha2 extends Pai {
function
__construct()
{
echo
"Eu também sou filha de " , get_parent_class('filha2') , "\n";
}
}

$foo = new Filha();
$bar = new Filha2();

?>

O exemplo acima produzirá:

Eu sou filha de Pai
Eu também sou filha de Pai

Veja Também

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User Contributed Notes 7 notes

up
6
yukal dot alexander at gmail dot com
5 years ago
An output of the entire inheritance chain using closures, recursion, and OOP

class ParentClass {
public static function getChain() {
$chain = null;
return $function = function($className='') use (& $chain, & $function) {
if (empty($className))
$className = static::class;

if (empty($chain))
$chain = $className;

$parent = get_parent_class($className);

if ($parent !== false) {
$chain .= " > {$parent}";
return $function($parent);
}

return $chain;
};
}
}

class Child extends ParentClass {}
class SubChild extends Child {}
class Sub2 extends SubChild {}
class Sub3 extends Sub2 {}
class Sub4 extends Sub3 {}
class Sub5 extends Sub4 {}
class Sub6 extends Sub5 {}
class Sub7 extends Sub6 {}

printf("%s\n", Sub7::getChain()());

$getChain = Sub7::getChain();
printf("%s\n", $getChain('Sub3'));

Output is:
Sub7 > Sub6 > Sub5 > Sub4 > Sub3 > Sub2 > SubChild > Child > ParentClass
Sub3 > Sub2 > SubChild > Child > ParentClass
up
1
jake at qzdesign dot co dot uk
4 years ago
Note that from PHP 5.5 you can also use `parent::class` from within a method, e.g.

<?php
function child()
{
echo
"I'm ", parent::class, "'s son\n";
}
?>

Looks a bit tidier and technically probably more optimal, as it avoids a function call lookup.
up
1
falundir at gmail dot com
11 years ago
You can use this function to find common parent of multiple objects or classes.

<?php
/**
* Returns name of the first (in class hierarchy) common parent class of all provided objects or classes.
* Returns FALSE when common class is not found.
*
* @param mixed $objects Array that can contain objects or class names.
* @return mixed
*/
function get_first_common_parent($objects) {
$common_ancestors = null;
foreach(
$objects as $object) {
if (
is_object($object)) {
$class_name = get_class($object);
} else {
$class_name = $object;
}

$parent_class_names = array();
$parent_class_name = $class_name;
do {
$parent_class_names[] = $parent_class_name;
} while(
$parent_class_name = get_parent_class($parent_class_name));

if (
$common_ancestors === null) {
$common_ancestors = $parent_class_names;
} else {
$common_ancestors = array_intersect($common_ancestors, $parent_class_names);
}
}

return
reset($common_ancestors);
}
?>

Example:

<?php
class A {
}

class
B extends A {
}

class
D extends B {
}

class
E extends B {
}

class
C extends A {
}

class
F extends C {
}

class
G extends F {
}

class
H {
}

//returns "A"
get_first_common_parent(array('G', 'E'));

//returns "F"
get_first_common_parent(array(new G(), 'F'));

//returns false (no common parent)
get_first_common_parent(array('C', 'H'));

//returns false (non-existent class provided)
get_first_common_parent(array(new B(), 'X'));
?>
up
1
levu
12 years ago
I wrote a simple function doing the reverse thing: get the children:

<?php
function get_child($instance, $classname) {
$class = $classname;
$t = get_class($instance);
while ((
$p = get_parent_class($t)) !== false) {
if (
$p == $class) {
return
$t;
}
$t = $p;
}
return
false;
}

abstract class
A {
function
someFunction() {
return
get_child($this, __CLASS__);
}
}

class
B extends A {

}

class
C extends B {

}

$c = new C();
echo
$c->someFunction(); //displays B

?>
up
0
ssb45 at cornell dot edu
15 years ago
"'If called without parameter outside object' What on earth does that mean?"

There are two places this could be called:
1. From within a member function of an object. In this case, it may be called with no parameters and will return the parent class of the object owning the member function. (If the parameter is included, then it will return the parent class of the specified class as normal.)

2. From outside an object (i.e., global or function scope). In this case, PHP doesn't know what class you're talking about if you don't include a parameter, so it returns FALSE. (But, of course, it works if you specify the class with the parameter.)
up
0
matt-php at DONT-SPAM-ME dot bitdifferent dot com
19 years ago
PHP (4 at least, dunno about 5) stores classnames in lower case, so:

<?PHP

class Foo
{
}

class
Bar extends Foo
{
}

echo
get_parent_class('Bar');

echo
"\n";

echo
get_parent_class('bar');

?>

will output:

foo
foo
up
0
radu dot rendec at ines dot ro
19 years ago
If the argument obj is a string and the class is not defined, then the function returns FALSE.

If the argument obj is an object created from a class with no ancestors (or a string representing a class with no ancestors), then the function returns FALSE.
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