I created this library to allow Enum to be used in many situations.
This library has the following advantages:
- Multiple values can be declared per enumerator
- You can declare Enum from various data sources, such as class constant, DB, or configuration file
- PHP ^7.4
composer require ynkt/enumEnum is an abstract class needs to be extended to use.
The following code uses class constant for the declaring Enum.
Notes
- Use protected visibility when writing the __constructor()
- Do not declare the methods that has the same name of the enumerator name
use Ynkt\Enum\Enum;
/**
* Class Status
*/
class Status extends Enum
{
private const READY = 'Ready';
private const IN_PROGRESS = 'In Progress';
private const DONE = 'Done';
private string $text;
// The argument of __constructor() is automatically assigned to the value of the enumerator
protected function __construct(string $text) { $this->text = $text; }
public function text(): string { return $this->text; }
}// Provided by this library
Status::values(); // Returns instances of the Enum class of all Enumerators
Status::first(); // Returns the first instance
Status::first(callable $closure); // Returns the first instance that passes a given truth
Status::has(callable $closure); // Tests an instance exists that passes a given truth
// Provided by the user declaration
// This library automatically provide the static method whose name is same of the enumerators name.
// The following methods return an Enum instance.
Status::READY();
Status::IN_PROGRESS();
Status::DONE();Static methods that has the same name as the enumerator name are implemented by __callStatic().
Therefore, if you care about the IDE auto completion, I recommend using the phpdoc as follows:
/**
* Class Status
*
* @method static self READY()
* @method static self IN_PROGRESS()
* @method static self DONE()
*/
class Status extends Enum
{
private const READY = 'Ready';
private const IN_PROGRESS = 'In Progress';
private const DONE = 'Done';
// ...
}$status = Status::READY();
// Provided by this library
$status->name(); // Returns the name of the current enumerator (e.g.:'READY')
$status->ordinal(); // Returns the ordinal of the current enumerator (e.g.:0)
$status->declaringClass(); // Returns the declaring class of the current enumerator (e.g.:'Status')
$status->equals(Status::Ready()); // Tests enum instances are equal (e.g.:true)
// Provided by the user declaration
$status->text(); // Returns 'Ready'You can use classes that inherit from Enum for type hints.
function updateStatus(Status $status){
// ...
}
updateStatus(Status::READY());If you want to declare the multiple values per enumerator, you can assign an array.
class Color extends Enum
{
private const RED = ['#FF0000', [255, 0, 0]];
private const BLUE = ['#0000FF', [0, 0, 255]];
private const BLACK = ['#000000', [0, 0, 0]];
// The argument of __constructor() is automatically assigned to the value of the enumerator
protected function __construct(string $code, array $rgb) {}
// ...
}If you want to declare an Enum based on data that is not a class constant,
you can overwrite getConstants().
The following two ways of declaration are equivalent.
class ColorFromDataSource extends Enum
{
/**
* @overwrite
*/
protected static function getConstants(string $class): array
{
return [
'RED' => ['#FF0000', [255, 0, 0]],
'BLUE' => ['#0000FF', [0, 0, 255]],
'BLACK' => ['#000000', [0, 0, 0]],
];
}
// ...
}class Color extends Enum
{
private const RED = ['#FF0000', [255, 0, 0]];
private const BLUE = ['#0000FF', [0, 0, 255]];
private const BLACK = ['#000000', [0, 0, 0]];
// ...
}Using an identifier as a way to get an instance is a common pattern.
So, as a way to achieve this, I have prepared ByIdTrait to get an instance based on the ID.
class DayOfWeek extends Enum
{
use ByIdTrait;
private const MONDAY = 1;
private const TUESDAY = 2;
private int $id;
public function id(): int { return $this->id; }
// ...
}
// You can use byId() to get the Enum instance.
$dayOfWeek = DayOfWeek::byId(1);
$dayOfWeek->equals(DayOfWeek::MONDAY()); // Returns trueI think the implementation of the ByIdTrait will be helpful when you get an instance based on some identifiers.