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get_declared_classes

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get_declared_classesErmittelt die Namen der definierten Klassen

Beschreibung

array get_declared_classes ( void )

Ermittelt die Namen der definierten Klassen

Rückgabewerte

Liefert ein Array mit den Namen der zur Zeit definierten Klassen.

Hinweis:

Bitte beachten Sie, dass je nachdem, welche Extensions in Ihrer PHP-Installation einkompiliert oder geladen sind, weitere Klassen vordefiniert sein können. Dies bedeutet, dass Sie keine eigenen Klassen mit dem gleichen Namen anlegen können. Eine Liste der möglicherweise vordefinierten Klassen finden Sie im Anhang Predefined Classes

Beispiele

Beispiel #1 get_declared_classes()-Beispiel

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

Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:

Array
(
    [0] => stdClass
    [1] => __PHP_Incomplete_Class
    [2] => Directory
)

Siehe auch


8 BenutzerBeiträge:
- Beiträge aktualisieren...
dcahh at gmx de
29.02.2008 18:23
This function considers only classes and subclasses. Not subsubclasses.

In fact I have code that provides an abstract class and then classes using this abstract class. Further I have subclasses to my concrete classes - which is why my subclasses are not listed within the returned array.
dexen + goofy _ pl
25.09.2007 20:32
Summary:
 * in PHP 5.1 class names have case preserved
 * contrary, in PHP 4.4 class names are downcased, withe exception of a few build-in ones

The get_declared_classes() funcition returns the list of names with case preserved, as of PHP 5.1 series (prolly 5.0 too, but i have no way to test it right now). Since PHP generally is caseless in regard to names of classes, this may come at a surprise. Also, this could potentially break older code asssuming downcased list.

Take extra care when  checking for existence of a class. Following example is, potentially, error prone: <?php in_array( $className, $classget_declared_classes() ) ?>

A sure-fire (while slower) way would be to iterate over the array and normalize case to, say, lower:

<?php
$exists
= FALSE;
$className = strtolower( $className );
foreach (
get_declared_classes() as $c ) {
    if (
$className === strtolower( $c ) ) {
       
$exists = TRUE;
        break;
    }
}
?>

Optimization of the above snippet is left as a simple excercise to the reader ;)
-- dexen deVries
matt at mattsoft dot net
21.12.2005 11:58
classes can't be unloaded. probably not very practical to implement that in a future version. I wouldn't go out of my way to do it if I were zend. you're better off finding a workaround. it's better programming technique to find a way around having to do that anyway.

http://www.zend.com/zend/week/week223.php#Heading10

22.03.2005 18:16
Regarding note of 3-21:

<?php

class myclass {}

$class = 'myclass';
$instance = new $class();

?>

This function could also be used to determine the names of classes defined in a particular file by calling it before and after include. It's hardly a pointless function.
matt-php at DONT-SPAM-ME dot bitdifferent dot com
1.11.2004 16:41
The array returned by this function will be in the order the classes were defined / included / required and this order does not appear to change.

For example:

<?PHP

//define classone
class classone { }

//define classtwo
class classtwo { }

//This will show X classes (built-ins, extensions etc) with
//classone and classtwo as the last two elements

print_r(get_declared_classes());

//define classthree
class classthree { }

//...and four
class classfour { }

//Shows the same result as before with class three and four appended
print_r(get_declared_classes());

?>

Output:

Array
(
   [0] => stdClass
   [1] .... other defined classes....
   [10] => classone
   [11] => classtwo
 )

and...

Array
(
   [0] => stdClass
   [1] .... other defined classes....
   [10] => classone
   [11] => classtwo
   [12] => classthree
   [13] => classfour
)
Jazeps Basko
7.02.2004 20:52
In PHP5, you don't get declared interfaces by calling this function!!!
To get interfaces you should use get_declared_interfaces(). However, to check if an interface is already defined, you should use class_exists()! This is strange, but PHP team does not think so.
smokey
21.03.2003 0:06
you cannot remove them. they are "defined", which happens when the class is being loaded from the parser. you just deleted an instance of a class.
Leigh Purdie
23.01.2003 10:01
Note that classes remain in the declared list, even when their associated object is undef'd.

eg:
    $object = new MyClass;
    print_r(get_declared_classes());

    undef($object);
    print_r(get_declared_classes());

- the two print_r's will return the same data.
Not sure how to remove a class from the declared list.



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