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Classkit> <Fonctions Classes/Objets
Last updated: Fri, 29 Aug 2008

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property_exists

(PHP 5 >= 5.1.0)

property_exists Vérifie si un objet ou une classe a une propriété

Description

bool property_exists ( mixed $class , string $property )

Cette fonction vérifie si la propriété property existe dans la classe spécifiée (et si elle est accessible de la portée courante).

Note: À l'opposé de la fonction isset(), property_exists() retourne TRUE même si la propriété a une valeur NULL.

Liste de paramètres

class

Le nom de la classe ou un objet de la classe à tester

property

Le nom de la propriété

Valeurs de retour

Retourne TRUE si la propriété existe, FALSE si elle n'existe pas et NULL si une erreur survient.

Exemples

Exemple #1 Exemple avec property_exists()

<?php

class myClass {
    public 
$mine;
    private 
$xpto;

    static function 
test() {
        
var_dump(property_exists('myClass''xpto')); // true, elle peut être accessible par ici
    
}
}

var_dump(property_exists('myClass''mine'));   //true
var_dump(property_exists(new myClass'mine')); //true
var_dump(property_exists('myClass''xpto'));   //false, non publique
myClass::test();

?>

Voir aussi



Classkit> <Fonctions Classes/Objets
Last updated: Fri, 29 Aug 2008
 
add a note add a note User Contributed Notes
property_exists
peter at nonumber dot nl
27-Aug-2008 11:48
The above PHP4 function did not work for me. This does:

<?php
if ( !function_exists( 'property_exists' ) ) {
    function
property_exists( $class, $property ) {
        if (
is_object( $class ) ) {
           
$vars = get_object_vars( $class );
        } else {
           
$vars = get_class_vars( $class );
        }
        return
array_key_exists( $property, $vars );
    }
}
?>
rayro at gmx dot de
12-Nov-2007 01:49
To check the existance of a property from outside the scope (even if it's not accessible) try/consider the following:

<?php
function property_exists_safe($class, $prop)
{
 
$r = property_exists($class, $prop);
  if (!
$r) {
   
$x = new ReflectionClass($class);
   
$r = $x->hasProperty($prop);
  }
  return
$r;
}

class
myClass {
    public
$mine;
    private
$xpto;

    static function
test1() {
       
// true, it can be accessed from here
       
var_dump(property_exists('myClass', 'xpto'));
    }

    static function
test2() {
       
// true, it can be accessed from everywhere!
       
var_dump(property_exists_safe('myClass', 'xpto'));
    }
}

var_dump(property_exists('myClass', 'mine')); //true
var_dump(property_exists(new myClass, 'mine')); //true
var_dump(property_exists('myClass', 'xpto')); //false, isn't public
myClass::test1();
echo(
"\n");
var_dump(property_exists_safe('myClass', 'mine')); //true
var_dump(property_exists_safe(new myClass, 'mine')); //true
var_dump(property_exists_safe('myClass', 'xpto')); //true
myClass::test2(); //true
?>

bool(true)
bool(true)
bool(false)
bool(true)

bool(true)
bool(true)
bool(true)
bool(true)
caist at caist dot com
15-Oct-2007 03:19
A niet way to copy properties from one object to another avoiding stuff like:

$obj2 -> prop1 = $obj1 -> prop1;
$obj2 -> prop2 = $obj1 -> prop2;
$obj2 -> prop3 = $obj1 -> prop3;

...is this loop through all properties:

// copies all property values from obj1 to obj2
foreach ($obj1 as $prop_name => $prop_value)
{
    if (property_exists(get_class($obj2), $prop_name))
                 $obj2 -> {$prop_name} = $prop_value;
}
K
13-Jul-2007 10:11
to ssettl2 at google's mail >

1) Use self:: in static methods : http://php.net/language.oop5.static

2) Under the description title of this page : "This function checks if the given property exists in the specified class (and if it is ACCESSIBLE FROM THE CURRENT SCOPE)."

This is normal behaviour in PHP5.

Regards
Alan71
07-Aug-2006 07:57
This function is case-sensitive, so :

<?php
class Test {
   public
$property;
  
   public
foo() { echo($property); }
}

property_exists('Test', 'property');   // will return true
property_exists('Test', 'Property');   // will return false
?>

(under PHP5.1.2)
jcaplan at bogus dot amazon dot com
08-Jun-2006 11:35
The documentation leaves out the important case of new properties you add to objects at run time.  In fact, property_exists will return true if you ask it about such properties.

<?
class Y {}
$y = new Y;

echo isset(
$y->prop ) ? "yes\n" : "no\n"; // no;
echo property_exists( 'Y', 'prop' ) ? "yes\n" : "no\n"; // no
echo property_exists( $y, 'prop' ) ? "yes\n" : "no\n"; // no

$y->prop = null;

echo isset(
$y->prop ) ? "yes\n" : "no\n"; // no;
echo property_exists( 'Y', 'prop' ) ? "yes\n" : "no\n"; // no
echo property_exists( $y, 'prop' ) ? "yes\n" : "no\n"; // yes
?>
Pete W
01-Jun-2006 08:52
In a similar vein to the previous note, To check in PHP4 if an object has a property, even if the property is null:

<?php

if(array_key_exists('propertyName',get_object_vars($myObj)))
{
 
// ..the property has been defined

?>
timshel
15-Nov-2005 01:20
I haven't tested this with the exact function semantics of 5.1, but this code should implement this function in php < 5.1:

<?php
if (!function_exists('property_exists')) {
  function
property_exists($class, $property) {
    if (
is_object($class))
     
$class = get_class($class);

    return
array_key_exists($property, get_class_vars($class));
  }
}
?>

Classkit> <Fonctions Classes/Objets
Last updated: Fri, 29 Aug 2008
 
 
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