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@NogDogFeb 05.2012 — #I'm not 100% sure I understand what you mean by "the change doesn't go through to the parent class".
A child class inherits properties and methods from its parent class, but that relationship is only a class definition thing: it has nothing to do with [i]objects[/i] instantiated from either class -- which will know no more about each other than any other two objects would.
Or I'm misunderstanding what you're asking?@NogDogFeb 05.2012 — #Nope. There is no connection between the object instantiated from class A and that instantiated from class B. They don't know anything about each other (unless you tie them together, such as by having one of class B's variables contain an [i]object[/i] of class A -- and in that case only that specific instance of class A would be affected.)
Perhaps what you're looking for in this case is a [i]static[/i] class variable? (However, note that it then "belongs" to [i]all[/i] instances.)
[RESOLVED] OOP: Child Class Doesn’t Update Parent Variable
I’m fairly new to Object Oriented Programming, but I’m learning slowly. Basically what I have here is a parent class that calls a child class’s method which is supposed to update the parent class’s array ($this->lang). However when I add more data to the array in the child class, the change doesn’t go through to the parent class.
[B][SIZE=”3″]Rough Example:
[code=php]
class ClassA
{
protected $array;
public function __construct
{
$this->array = array();
}
protected function init()
{
$class2 = new ClassB;
$class2->insert_into_array();
}
}
class ClassB extends ClassA
{
public function __construct()
{
parent::__construct();
}
protected function insert_into_array()
{
array_push($this->array, $database_entry);
}
}
$heyo = new ClassA;
$heyo->init();
/*
I’m writing this code directly into this post and don’t have time to check it over carefully,
but it gives you an idea of what I’m trying to accomplish.
*/
Now if I print_r the array in the child class’s insert_into_array() method, it shows up as expected. But if I print_r the array in the parent class’s init() method after calling the insert_into_array() method, it comes back empty.
So, the question is, how do I update the array in the parent class?
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@NogDogFeb 05.2012 — #I'm not 100% sure I understand what you mean by "the change doesn't go through to the parent class".A child class inherits properties and methods from its parent class, but that relationship is only a class definition thing: it has nothing to do with [i]objects[/i] instantiated from either class -- which will know no more about each other than any other two objects would.
Or I'm misunderstanding what you're asking?
0
@NogDogFeb 05.2012 — #Nope. There is no connection between the object instantiated from class A and that instantiated from class B. They don't know anything about each other (unless you tie them together, such as by having one of class B's variables contain an [i]object[/i] of class A -- and in that case only that specific instance of class A would be affected.)Perhaps what you're looking for in this case is a [i]static[/i] class variable? (However, note that it then "belongs" to [i]all[/i] instances.)
[code=php]
<?php
class ClassA
{
protected static $array = array();
public function getArray()
{
return self::$array;
}
}
class ClassB extends ClassA
{
public function insertIntoArray($value)
{
array_push(self::$array, $value); // note use of self::
}
}
$testA = new ClassA();
$testB = new ClassB();
$testB->insertIntoArray('foo');
$testB->insertIntoArray('bar');
echo "<pre>".print_r($testA->getArray(), true)."</pre>n";
echo "<pre>".print_r($testB->getArray(), true)."</pre>n";
// However...
$testC = new ClassA();
$testD = new ClassB();
// static array already populated, since all objects of these classes will share it
echo "<pre>".print_r($testA->getArray(), true)."</pre>n";
echo "<pre>".print_r($testB->getArray(), true)."</pre>n";
[/code]