PHP and Enumerations

Question

I know that PHP doesn\'t have native Enumerations. But I have become accustomed to them from the Java world. I would love to use enums as a way to give predefined values whi

Answer 1

Some good solutions on here!

Here's my version.

• It's strongly typed
• It works with IDE auto-completion
• Enums are defined by a code and a description, where the code can be an integer, a binary value, a short string, or basically anything else you want. The pattern could easily be extended to support orther properties.
• It asupports value (==) and reference (===) comparisons and works in switch statements.

I think the main disadvantage is that enum members do have to be separately declared and instantiated, due to the descriptions and PHP's inability to construct objects at static member declaration time. I guess a way round this might be to use reflection with parsed doc comments instead.

The abstract enum looks like this:

code = $code;
        $this->description = $description;
    }

    public function getCode()
    {
        return $this->code;
    }

    public function getDescription()
    {
        return $this->description;
    }
}

Here's an example concrete enum:

Which can be used like this:

getCode().' : '.EMyEnum::$MY_FIRST_VALUE->getDescription().PHP_EOL.PHP_EOL;

var_dump(EMyEnum::getAllMembers());

echo PHP_EOL.EMyEnum::getByCode(2)->getDescription().PHP_EOL;

And produces this output:

1 : My first value

array(3) {  
  [1]=>  
  object(EMyEnum)#1 (2) {  
    ["code":"AbstractEnum":private]=>  
    int(1)  
    ["description":"AbstractEnum":private]=>  
    string(14) "My first value"  
  }  
  [2]=>  
  object(EMyEnum)#2 (2) {  
    ["code":"AbstractEnum":private]=>  
    int(2)  
    ["description":"AbstractEnum":private]=>  
    string(15) "My second value"  
  }  
  [3]=>  
  object(EMyEnum)#3 (2) {  
    ["code":"AbstractEnum":private]=>  
    int(3)  
    ["description":"AbstractEnum":private]=>  
    string(14) "My third value"  
  }  
}

My second value