LXXXII. Object property and method call overloading

Uvod

The purpose of this extension is to allow overloading of object property access and method calls. Only one function is defined in this extension, overload() which takes the name of the class that should have this functionality enabled. The class named has to define appropriate methods if it wants to have this functionality: __get(), __set() and __call() respectively for getting/setting a property, or calling a method. This way overloading can be selective. Inside these handler functions the overloading is disabled so you can access object properties normally.

Pozor

Ta razširitev je EKSPERIMENTALNA. Delovanje razširitve, imena funkcij in vse ostalo v zvezi s to razširitvijo se lahko spremeni brez opozorila v bodočih verzijah PHP-ja. Uporabljate jo na lastno odgovornost.

Pozor

This extension is not a part of PHP 5. PHP 5 supports __get(), __set() and __call() natively. See PHP 5 migration chapter for more information.

Zahteve

Te funkcije so na voljo znotraj standardnega modula, ki je vedno na voljo.

Namestitev

In order to use these functions, you must compile PHP with the --enable-overload option. Starting with PHP 4.3.0 this extension is enabled by default. You can disable overload support with --disable--overload.

The windows version of PHP has built in support for this extension. You do not need to load any additional extension in order to use these functions.

Opomba: Builtin support for overload is available with PHP 4.3.0.

Nastavitve

Ta razširitev ne določa nastavitvenih direktiv.

Tipi sredstev

Ta razširitev ne določa nobenega tipa sredstev.

Predefinirane konstante

Ta razširitev ne definira nobene konstante.

Primeri

Some simple examples on using the overload() function:

Primer 1. Overloading a PHP class

<?php

class OO {
    var
$a = 111;
    var
$elem = array('b' => 9, 'c' => 42);

    
// Callback method for getting a property
    
function __get($prop_name, &$prop_value)
    {
        if (isset(
$this->elem[$prop_name])) {
            
$prop_value = $this->elem[$prop_name];
            return
true;
        } else {
            return
false;
        }
    }

    
// Callback method for setting a property
    
function __set($prop_name, $prop_value)
    {
        
$this->elem[$prop_name] = $prop_value;
        return
true;
    }
}

// Here we overload the OO object
overload('OO');

$o = new OO;
echo
"\$o->a: $o->a\n"; // print: $o->a: 111
echo "\$o->b: $o->b\n"; // print: $o->b: 9
echo "\$o->c: $o->c\n"; // print: $o->c: 42
echo "\$o->d: $o->d\n"; // print: $o->d:

// add a new item to the $elem array in OO
$o->x = 56;

// instantiate stdclass (it is built-in in PHP 4)
// $val is not overloaded!
$val = new stdclass;
$val->prop = 555;

// Set "a" to be an array with the $val object in it
// But __set() will put this in the $elem array
$o->a = array($val);
var_dump($o->a[0]->prop);

?>

Kazalo
overload -- Enable property and method call overloading for a class