mirror of
https://github.com/restoreddev/phpapprentice.git
synced 2025-10-24 19:36:04 +02:00
60 lines
1.1 KiB
Markdown
60 lines
1.1 KiB
Markdown
Whenever you create an object in PHP, you put parentheses after the class name.
|
|
In the previous examples, we always left the parentheses empty.
|
|
```php
|
|
<?php
|
|
|
|
class Hat {
|
|
public $color;
|
|
|
|
public function setColor($color)
|
|
{
|
|
$this->color = $color;
|
|
}
|
|
}
|
|
|
|
$hat = new Hat();
|
|
```
|
|
|
|
However, you can actually pass data into the parentheses like a function.
|
|
The data will be passed to a special function on the class called a constructor.
|
|
```php
|
|
class Ballcap
|
|
{
|
|
public $color;
|
|
|
|
public function __construct($color)
|
|
{
|
|
$this->color = $color;
|
|
}
|
|
}
|
|
```
|
|
|
|
A constructor is not required, but can make creating a new object easier.
|
|
They are usually used to define the initial value of a property.
|
|
Instead of writing:
|
|
```php
|
|
$hat = new Hat();
|
|
$hat->setColor('Red');
|
|
```
|
|
|
|
You can write:
|
|
```php
|
|
$ballcap = new Ballcap('Blue');
|
|
```
|
|
|
|
Constructors do not return values because the return value is a always a new object.
|
|
```php
|
|
class Tophat
|
|
{
|
|
public function __construct($color)
|
|
{
|
|
return $color;
|
|
}
|
|
}
|
|
```
|
|
|
|
`$tophat` now holds an instance of `Tophat`, not the string "Grey".
|
|
```php
|
|
$tophat = new Tophat('Grey');
|
|
```
|