OOP - Class Properties

[benanamen]

Aside from setting a default value, is there any reason a class needs properties or a property with no default value?

 

Here are two examples I am working with. One has a default car color from a property that gets changed (overwritten?), the other just sets the color with no property.

 

Property with default color value

<?php
class Car {
  public $color = 'red';
}

$bmw = new Car ();
echo $bmw -> color; // red

$bmw -> color = 'blue';
echo "<br>";
echo $bmw -> color; // blue

Class with no property sets color

<?php
class Car {
}

$bmw = new Car ();
$bmw -> color = 'blue';
echo $bmw -> color; // blue

[requinix]

You should define properties, with or without defaults. Putting them in the class helps to document what the properties are, and personally I give defaults (even just 0 or empty strings) to be clear what type of values it will have.

 

I mean, look at Car:

class Car {
  public $color = 'red';
}

class Car {
  public $color;
}

class Car {
}

The first has an obvious property, and the default may or may not make sense but at least you get a feel for it. (In this example I don't think having "red" makes sense.) The second has an obvious property but it's not clear whether it might have a string, int, or object as its value. (Docblocks are good for that too.) The third is completely unhelpful.