PHP: Calling another class' method - php

Question

I'm still learning OOP so this might not even be possible (although I would be surprised if so), I need some help calling another classes method.
For example in ClassA I have this method:
function getName()
{
return $this->name;
}
now from ClassB (different file, but in the same directory), I want to call ClassA's getName(), how do I do that? I tried to just do an include() but that does not work.
Thanks!

Answer 1

//file1.php
<?php
class ClassA
{
private $name = 'John';
function getName()
{
return $this->name;
}
}
?>
//file2.php
<?php
include ("file1.php");
class ClassB
{
function __construct()
{
}
function callA()
{
$classA = new ClassA();
$name = $classA->getName();
echo $name; //Prints John
}
}
$classb = new ClassB();
$classb->callA();
?>

Answer 2

If they are separate classes you can do something like the following:
class A
{
private $name;
public function __construct()
{
$this->name = 'Some Name';
}
public function getName()
{
return $this->name;
}
}
class B
{
private $a;
public function __construct(A $a)
{
$this->a = $a;
}
function getNameOfA()
{
return $this->a->getName();
}
}
$a = new A();
$b = new B($a);
$b->getNameOfA();
What I have done in this example is first create a new instance of the A class. And after that I have created a new instance of the B class to which I pass the instance of A into the constructor. Now B can access all the public members of the A class using $this->a.
Also note that I don't instantiate the A class inside the B class because that would mean I tighly couple the two classes. This makes it hard to:
unit test your B class
swap out the A class for another class

Answer 3

You would need to have an instance of ClassA within ClassB or have ClassB inherit ClassA
class ClassA {
public function getName() {
echo $this->name;
}
}
class ClassB extends ClassA {
public function getName() {
parent::getName();
}
}
Without inheritance or an instance method, you'd need ClassA to have a static method
class ClassA {
public static function getName() {
echo "Rawkode";
}
}
--- other file ---
echo ClassA::getName();
If you're just looking to call the method from an instance of the class:
class ClassA {
public function getName() {
echo "Rawkode";
}
}
--- other file ---
$a = new ClassA();
echo $a->getName();
Regardless of the solution you choose, require 'ClassA.php is needed.

Answer 4

File 1
class ClassA {
public $name = 'A';
public function getName(){
return $this->name;
}
}
File 2
include("file1.php");
class ClassB {
public $name = 'B';
public function getName(){
return $this->name;
}
public function callA(){
$a = new ClassA();
return $a->getName();
}
public static function callAStatic(){
$a = new ClassA();
return $a->getName();
}
}
$b = new ClassB();
echo $b->callA();
echo $b->getName();
echo ClassB::callAStatic();