PHP assign a value to a variable (globa) from within the classs - php

Question

I have a small PHP snippet.
How can I assign a new value to my global from within a main class?
Example:
$GlobalValue = 0;
class SampleModuleController extends SampleController {
public function doSomething() {
$NewValue = 1;
$GlobalValue = $NewValue
}
}
echo $GlobalValue;
//This always echo's 0, When I try to output or print outside the class or use somewhere above in the php code.
//I need to be able to assign the new value from within my class
//and the function doSomething so it should be 1

Answer 1

You can pass parameter as reference in the method doSomething() and then call that function passing your variable $GlobalValue. However it's not very recommended to have global variables. You should consider change your code to more OOP.
$GlobalValue = 0;
class SampleModuleController {
private $newValue = 3;
public function doSomething(&$variable) {
$variable = $this->newValue;
}
}
$ModuleController = new SampleModuleController();
$ModuleController->doSomething($GlobalValue);
echo $GlobalValue; //print 1

Answer 2

If i understood it right what you are trying to do can be achieved quite easily with this:
global $GlobalValue;
$GlobalValue = 0;
class SampleModuleController {
public function doSomething() {
global $GlobalValue;
$NewValue = 1;
$GlobalValue = $NewValue;
}
}
$ModuleController = new SampleModuleController();
$ModuleController->doSomething();
echo $GlobalValue; //print 1
They key is in the "global" keyword (which is the same as accessing the $GLOBAL["your_var_name"] container.
Beside this, as others said relying on global variables should be discouraged.