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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.
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In the previous examples, we always left the parentheses empty.
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```php
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<?php
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class Hat {
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public $color;
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public function setColor($color)
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{
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$this->color = $color;
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}
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}
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$hat = new Hat();
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```
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However, you can actually pass data into the parentheses like a function.
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The data will be passed to a special function on the class called a constructor.
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```php
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class Ballcap
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{
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public $color;
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public function __construct($color)
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{
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$this->color = $color;
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}
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}
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```
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A constructor is not required, but can make creating a new object easier.
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They are usually used to define the initial value of a property.
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Instead of writing:
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```php
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$hat = new Hat();
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$hat->setColor('Red');
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```
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You can write:
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```php
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$ballcap = new Ballcap('Blue');
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```
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Constructors do not return values because the return value is a always a new object.
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```php
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class Tophat
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{
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public function __construct($color)
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{
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return $color;
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}
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}
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```
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`$tophat` now holds an instance of `Tophat`, not the color "Grey".
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```php
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$tophat = new Tophat('Grey');
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```
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