How to convert php enum to array?

I've got the following enum:

abstract class DaysOfWeek
{
    const Sunday = 0;
    const Monday = 1;
    // etc.
}

How can I modify the following function to generate an array based on the enum above?

public function getOptions()
{
    return [
        0 => 'Sunday',
        1 => 'Monday',
    ];
}

Isn't it better to use SplEnum for this purpose?

I'm not sure if it's better to use Splenum, but I know this can be done using ReflectionClass. Assuming you want getOptions to be defined in a class that extends DaysOfWeek, your code might look something like this:

abstract class DaysOfWeek
{
    const Sunday = 0;
    const Monday = 1;
    // etc.
}


class myClass extends DaysOfWeek {
    public function getOptions() {
            $oClass = new ReflectionClass(__CLASS__);
            $constants = $oClass->getConstants();
            $retval = array();
            foreach($constants as $name => $val) {
                    $retval[$val] = $name;
            }
            return $retval;
    }
}

$o = new myClass();
var_dump($o->getOptions());

EDIT: here's an even more compact and efficient version of the getOptions function which uses native PHP functions:

    public function getOptions() {
            $oClass = new ReflectionClass(__CLASS__);
            $constants = $oClass->getConstants();
            return(array_combine(array_values($constants), array_keys($constants)));
    }

EDIT 2: If getOptions is in a class that does NOT extend DaysOfWeek, you can simply refer to the classname like so:

class AnotherClass {
    public function getOptions() {
            $oClass = new ReflectionClass(DaysOfWeek);
            $constants = $oClass->getConstants();
            return(array_combine(array_values($constants), array_keys($constants)));
    }
}

$o = new AnotherClass();
var_dump($o->getOptions());