brunojunior/simple-enum

Abstract class to simulate enum with label in PHP

v1.0 2018-08-22 14:57 UTC

Requires

• php: >=7.1.0
• danielstjules/stringy: ^3.1

MIT

• Bruno Desprez

README

Abstract class to simulate enum with label in PHP

How to install

composer require brunojunior/simple-enum

How to use

You have to create a class which extends SimpleEnum\Enum.

The simpliest enum

This enum will automatically generate labels thanks to the constants name. Here, you'll have those labels «First value», «Second value» and «Third value».

<?php
class SimpleEnum extends \SimpleEnum\Enum
{
    const FIRST_VALUE = 0;
    const SECOND_VALUE = 1;
    const THIRD_VALUE = 2;
}

A simple enum with defined labels

In this enum, the user want to change default labels.

<?php
class LabeledEnum extends \SimpleEnum\Enum
{
    const FIRST_VALUE = 0;
    const SECOND_VALUE = 1;
    const THIRD_VALUE = 2;

    /**
     * Specify the labels
     */
    protected static function defineList(): void
    {
        static::addEnum(static::FIRST_VALUE, 'My first value');
        static::addEnum(static::SECOND_VALUE, 'This is the second value');
        static::addEnum(static::THIRD_VALUE, 'Hey! 3rd value!');
    }
}

A more complex enum with extra fonctionnality

In this enum, the user want to change default label and add some extra features.

<?php
class ComplexEnum extends \SimpleEnum\Enum
{
    const FIRST_VALUE = 0;
    const SECOND_VALUE = 1;
    const THIRD_VALUE = 2;
    
    /**
     * A property
     */
    private $prop;

    /**
     * Specify the labels
     */
    protected static function defineList(): void
    {
        static::addEnum(static::FIRST_VALUE, 'My first value')->setProp(42);
        static::addEnum(static::SECOND_VALUE, 'This is the second value')->setProp(0);
        static::addEnum(static::THIRD_VALUE, 'Hey! 3rd value!')->setProp(-1);
    }

    /**
     * @param int $value
     * @return ComplexEnum
     */
    private function setProp(int $value):self
    {
        $this->prop = $value;
        return $this;
    }

    /**
     * @return int|null
     */
    public function getProp():?int
    {
        return $this->prop;
    }
    
    /**
     * @return string
     */
    public function doStuffWithProp():string
    {
        if ($this->prop === 42) {
          return "This is the answer to life the universe and everything";
        }
        return "I don't know";
    }
}

Available methods

Enum::getList()

This method will return an array with constants value as keys and the associated Enum instance as values.

Enum::getLabels()

This method will return an array with constants value as keys and the label as values. It can be useful for HTML select options.

Enum::getLabelById()

This method will return the label for a specific key. If the key is unknown it will raise SimpleEnum\UnknownEumException.

Enum::getInstance()

This method will return an Enum instance for a specific key. If the key is unknown it will raise SimpleEnum\UnknownEumException.

enumInstance->getLabel()

This method will return the label of a specific instance.

enumInstance->setLabel($label)

This method allows you to override the default label.

enumInstance->resetLabel()

This method will reset the default label of the instance.

enumInstance->getKey()

This method will return the key of the instance.

enumInstance->is(int $key)

This method will check if the instance has the same key.

enumInstance->equals(Enum $anotherInstance)

This method will check if the two instances have the same key.

How to compare

Using the ==

This way to compare is really simple. You can do something like this :

$receivedValue = 2;
SimpleEnum::getInstance(SimpleEnum::THIRD_VALUE) == $receivedValue;

Using the is method

$receivedValue = 2;
SimpleEnum::getInstance(SimpleEnum::THIRD_VALUE)->is($receivedValue);