PHP class: Global variable as property in class

You can use the global keyword to access a global variable inside a class. Here's an example:

<?php

$x = 1;

class MyClass
{
  public $y;

  public function __construct()
  {
    global $x;
    $this->y = $x + 1;
  }
}

$obj = new MyClass();
echo $obj->y; // Outputs 2

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Keep in mind that using global variables in this way can make your code less modular and more difficult to maintain. It's generally a better practice to pass any variables that a class needs as arguments to its methods or to its constructor.