PHP Arrayable Interface

Question

I'm sure I read a while back about a new feature of PHP that was either a new magic method or a new interface so that you could implement Arrayable methods.

eg

interface Arrayable
{
    public function toArray();
}

Was I imagining it?

Solution 1

Was I imagining it?

Yes.

• There is no interface (PHP 5.4 or otherwise) within PHP for handling casting to an array.

• PHP 5.4.0 introduced the JsonSerializable interface, perhaps you're thinking of that?

• There's also a draft RFC (one of several related) that suggests a __toArray() method; see Request for Comments: Scalar Type Casting Magic Methods

Solution 2

It's not in PHP itself, but Laravel has an interface that is intended for that exact purpose:

<?php namespace Illuminate\Contracts\Support;

interface Arrayable {

    /**
     * Get the instance as an array.
     *
     * @return array
     */
     public function toArray();

}

Note: In Laravel v4 the namespace was Illuminate\Support\Contracts and the interface name was ArrayableInterface.

Solution 3

You are probably thinking of the iterator interface. If you create a class that implements this you can iterate over it as if it is an array. For example, you can use it in a foreach() loop.

Also take a look at the other predefined interfaces.

You can always write your own arrayable interface and then you can type hint for it or check it with instanceof (see example #4) as you indicated you wanted to do in your comment.

Solution 4

There's this (which is fairly useless IMO) http://php.net/manual/en/class.traversable.php

and also this (which does come in handy but always requires a type check before using it)

http://php.net/manual/en/function.iterator-to-array.php

But no way to handle object to array conversion implicitly.

View more solutions

Comments

[gawpertron]

php.net/manual/en/class.serializable.php has the same idea as the Arrayable interface. It's not about making an object traversable, but being able to return a representation of the object as an Array.

[gawpertron]

Or type casting to an array ie $foo = (array) $arrayableObject

[vascowhite]

Then just write a toArray() method. You are best placed to know how your object should be represented as an array. I don't think PHP could be expected to guess that for you.

[gawpertron]

I plan to, but to check if the object is an interfaceof of a standard interface would be tidy.

[gawpertron]

I was kind of thinking of a native interface that you could then typecast objects to an array i.e. $array = (array) $object;

[alexeydemin]

namespace Illuminate\Contracts\Support;

[jave.web]

@gawpertron btw you can do that, it will result in array of property values keyed by property names - you can then access public properties, private&protected are prefixed in this conversion - more on that here in official docs: php.net/manual/en/…