Accessing variables and methods outside of class definitions

Question

Suppose I have a php file along these lines:

<?php function abc() {  }  $foo = 'bar';  class SomeClass {  } ?> 

Is there anything special I have to do to use abc() and $foo inside SomeClass? I'm thinking along the lines of using global in a function to access variables defined outside the function.

(I'm new to OOP in PHP)

Answer 1

functions outside any class are global an can be called from anywhere. The same with variables.. just remember to use the global for the variables...

e.g

<?php function abc() {  }  $foo = 'bar';  class SomeClass {    public function tada(){      global $foo;       abc();      echo 'foo and '.$foo;  } } ?> 

Answer 2

Simply pass your variable to object instance through constructor or pass it to method when it's needed and remember to DON'T USE GLOBAL! ANYWHERE!

Why global is to be avoided?

The point against global variables is that they couple code very tightly. Your entire codebase is dependent on a) the variable name $config and b) the existence of that variable. If you want to rename the variable (for whatever reason), you have to do so everywhere throughout your codebase. You can also not use any piece of code that depends on the variable independently of it anymore. https://stackoverflow.com/a/12446305/1238574

You can use abc() everywhere because in PHP functions are globally accessible.

<?php function abc() {  }  $foo = 'bar';  class SomeClass {     private $foo;     public function __construct($foo) {         $this->foo = $foo;     }     public function doSomething() {         abc($this->foo);     } }  class OtherClass {     public function doSomethingWithFoo($foo) {         abc($foo);     } }  $obj = new SomeClass($foo); // voillea  // or  $obj2 = new OtherClass(); $obj2->doSomethingWithFoo($foo);