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'));
?>
get_parent_class
(PHP 4, PHP 5)
get_parent_class — オブジェクトの親クラスの名前を取得する
パラメータ
-
object -
調べたいオブジェクトあるいはクラスの名前。
返り値
object
がインスタンスあるいは名前であるクラスの親クラス名を返します。
注意:
オブジェクトが親を持たない場合や指定したクラスが存在しない場合は
FALSEを返します。
オブジェクトの外部からこのパラメータを省略してコールすると、
この関数は FALSE を返します
変更履歴
| バージョン | 説明 |
|---|---|
| 5.1.0 より前 |
オブジェクトの外部からパラメータなしでコールすると、
この関数は警告を発生したうえで NULL を返します。
|
| 5.0.0 以降 |
オブジェクトのメソッドからコールされた場合、パラメータ
object はオプションとなります。
|
| 4.0.5 以降 |
object が文字列の場合、
その名前のクラスの親クラスの名前を返します。
|
例
例1 get_parent_class() の使用例
<?php
class dad {
function dad()
{
// ロジックを実装する
}
}
class child extends dad {
function child()
{
echo "I'm " , get_parent_class($this) , "'s son\n";
}
}
class child2 extends dad {
function child2()
{
echo "I'm " , get_parent_class('child2') , "'s son too\n";
}
}
$foo = new child();
$bar = new child2();
?>
上の例の出力は以下となります。
I'm dad's son I'm dad's son too
falundir at gmail dot com
13-Apr-2012 10:27
Michael Torp Kaalund
07-Jun-2011 05:45
I have been playing with parent and child class, and I used this function to determine that which one was calling an function. I for an example it if you only want your parent class to be able to make an function call:
here is my example (by the way this example was inspired by another example fund on php.net):
<?php
class Parents {
public static $status; //This is the status
protected static $idCount;
protected $id;
function __construct() {
$this->id = ++self::$idCount;
self::$status = "tmp";
}
public function run($task) {
if(get_parent_class($this) == "") {
echo 'Command issued: '.$task.'<br>';
self::$status = $task;
}
}
public function __tostring() {
return "(".__class__.")id=".$this->id." status=".self::$status."<br>";
}
}
class Child extends Parents {
function __construct() {
parent::__construct();
self::$status = "tmp";
echo "Child construct<br>";
}
public function __tostring() {
return "(".__class__.")id=".$this->id." status=".self::$status."<br>";
}
}
$parent = new Parents();
echo $parent;
$child = new Child();
echo $child;
echo get_parent_class('Child')."<br>";
$parent->run("mtk");
echo $parent;
echo $child;
$child->run("mtk1");
echo $parent;
echo $child;
?>
which will produces somethink like:
(Parents)id=1 status=tmp
Child construct
(Child)id=2 status=tmp
Parents
Command issued: mtk
(Parents)id=1 status=mtk
(Child)id=2 status=mtk
(Parents)id=1 status=mtk
(Child)id=2 status=mtk
hopes it helps some one :D
levu
20-Apr-2011 08:36
I wrote a simple function doing the reverse thing: get the children:
<?php
function get_child($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 $c->someFunction(); //displays B
?>
michael at getsprink dot -- com
09-Apr-2009 12:28
This little snippet to get the inheritance tree might be useful to someone.
<?php
header("Content-Type: text/plain;");
class Top {
public function getParents($class=null, $plist=array()) {
$class = $class ? $class : $this;
$parent = get_parent_class($class);
if($parent) {
$plist[] = $parent;
/*Do not use $this. Use 'self' here instead, or you
* will get an infinite loop. */
$plist = self::getParents($parent, $plist);
}
return $plist;
}
}
class Middle extends Top {
}
class Bottom extends Middle {
}
$o = new Bottom();
print_r($o->getParents());
?>
ssb45 at cornell dot edu
14-May-2008 08:32
"'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.)
marcus at synchromedia dot co dot uk
16-Apr-2008 09:08
"If called without parameter outside object" What on earth does that mean?
What I can tell you, and that is not documented, is that if the object in question does not have an explicitly declared parent class, it does return boolean false. It doesn't for example return 'stdClass' on the basis that all objects are derived from that.
birkholz at web dot de
06-Oct-2005 05:01
tim at correctclick dot com wrote:
<quote>
A slightly more cryptic but faster get_ancestors function:
<?php
function get_ancestors ($class) {
for ($classes[] = $class; $class = get_parent_class ($class); $classes[] = $class);
return $classes;
}
?>
(The second part of the for is implicitly testing for $class != ""). Recursion is considerably slower than looping, so you probably want to use this function.
Hope someone finds it useful.
</quote>
I would prefer this version, because it will create no duplicates:
<?php
function get_ancestors ($class) {
$classes = array($class);
while($class = get_parent_class($class)) { $classes[] = $class; }
return $classes;
}
Greets, Dennis
?>
matt-php at DONT-SPAM-ME dot bitdifferent dot com
01-Nov-2004 07:52
PHP (4 at least, dunno about 5) stores classnames in lower case, so:
<?PHP
class Foo
{
}
class Bar extends Foo
{
}
echo get_parent_class('Bar');
echo "\n";
echo get_parent_class('bar');
?>
will output:
foo
foo
radu dot rendec at ines dot ro
07-Apr-2004 06:44
If the argument obj is a string and the class is not defined, then the function returns FALSE.
If the argument obj is an object created from a class with no ancestors (or a string representing a class with no ancestors), then the function returns FALSE.
tim at correctclick dot com
05-Apr-2003 07:48
A slightly more cryptic but faster get_ancestors function:
function get_ancestors ($class) {
for ($classes[] = $class; $class = get_parent_class ($class); $classes[] = $class);
return $classes;
}
(The second part of the for is implicitly testing for $class != ""). Recursion is considerably slower than looping, so you probably want to use this function.
Hope someone finds it useful.
eric dot brison at anakeen dot com
28-Jan-2002 04:14
To return all ancestors class of an object
function get_ancestors_class($classname) {
$father = get_parent_class($classname);
if ($father != "") {
$ancestors = get_ancestors_class($father);
$ancestors[] = $father;
}
return $ancestors;
}
example :
-----------
Class C {
}
Class B extends C {
}
Class A extends B {
}
print_r (get_ancestors_class("a"));
print_r (get_ancestors_class("b"));
example result :
---------------
Array
(
[0] => c
[1] => b
)
Array
(
[0] => c
)
