PHP Laravel using application class as an array instead of using attributes - php

Question

well, i'm wondering how they use the application class as an array
for example in application file
vendor/laravel/framework/src/illuminate/Container/Application.php
in magic methods __set and __get they use $this as an array
here is the code
/**
* Dynamically access container services.
*
* #param string $key
* #return mixed
*/
public function __get($key)
{
return $this[$key];
}
/**
* Dynamically set container services.
*
* #param string $key
* #param mixed $value
* #return void
*/
public function __set($key, $value)
{
$this[$key] = $value;
}
but i don't understand how this works without thorwing any errors
i have tried something like that but it give me the following error
Here is My Code
class Container{
public function __get($key){
return $this[$key];
}
public function __set($key,$val){
$this[$key] = $val;
}
}
$app = new Container();
$app->test = 'ok';
echo $app->test;
Fatal error: Cannot use object of type Container as array in C:\xampp\htdocs\test\test.php on line 10
Any explaination for this please ?
by the way i'm using laravel v4.2.12

Answer 1

Laravel's Illuminate\Container\Container class implements PHP's ArrayAccess interface, which provides the array access syntax to a class. To implement this interface, you must provide an implementation for the offsetExists(), offsetGet(), offsetSet(), and offsetUnset() methods. Once your class correctly implements the ArrayAccess interface, you can use the array access syntax.
This is just one example of an ArrayAccess implementation, but you can try something like this:
// note the implementation
class Container implements ArrayAccess {
protected $data = array();
public function offsetExists($offset) {
return array_key_exists($offset, $this->data);
}
public function offsetGet($offset) {
return $this->data[$offset];
}
public function offsetSet($offset, $value) {
$this->data[$offset] = $value;
}
public function offsetUnset($offset) {
unset($this->data[$offset]);
}
public function __get($key) {
return $this[$key];
}
public function __set($key, $val) {
$this[$key] = $val;
}
}
$app = new Container();
$app->test = 'ok';
echo $app->test.PHP_EOL.PHP_EOL.print_r($app, true);
You can also look at the Illuminate\Container\Container implementation to see how Laravel actually does it.