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Unit 8: Objects

$animal = new Animal(); Notes
With just that line of code, the object will be created, the constructor called and the lines of code
in it executed, which will cause our “I’m alive!” line to be outputted. However, as mentioned, a
big advantage of the constructor is the ability to pass parameters which can be used to initialize
member variables.

<?php

class Animal
{
public $name = “No-name animal”;
public function __construct($name)
{
$this->name = $name;

}
}
$animal = new Animal(“Bob the Dog”);
echo $animal->name;
?>
Declaring the constructor with parameters is just like declaring a regular function, and passing
the parameter(s) is much like calling a regular function, but of course with the “new” keyword
that we introduced earlier. A constructor can have as many parameters as you want.
Destructors
A destructor is called when the object is destroyed. In some programming languages, you have
to manually dispose of objects you created, but in PHP, it is handled by the Garbage Collector,
which keeps an eye on your objects and automatically destroys them when they are no longer
needed. Have a look at the following example, which is an extended version of our example.

<?php
class Animal
{
public $name = “No-name animal”;
public function __construct($name)
{
echo “I’m alive!”;

$this->name = $name;
}
public function __destruct()
{

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