PHP class implementing Serializable doesn't serialize

Question

What I was really looking for was a magic method __toArray for my class, but I guess such a thing doesn't exist, and the ArrayAccess interface doesn't match what I'm looking for.

I would like to be able to return a json_encoded representation of my object when serialize is called on it, instead of the traditional PHP string representation.

Here is an example of my code, which I can't get to work.

<pre>
<?php
class A implements Serializable {
    private $a,
        $b,
        $c;

    public function __construct () {
        $this->a = 1;
        $this->b = 2;
        $this->c = 3;
    }

    public function serialize () {
        return json_encode(array (
            'a' => $this->a,
            'b' => $this->b
        ));
    }

    public function unserialize ($serialized) {
    }
}

echo '<b>PHP version:</b> ',
    phpversion(),
    PHP_EOL,
    '<b>Serialized:</b> ',
    serialize(new A());
?>
</pre>

I know I'm implementing the interface correctly, because if I omit one of the methods, it displays an error. However, this is what my script returns:

PHP version: 5.4.14

Serialized: C:1:"A":13:{{"a":1,"b":2}}

If I instantiate an instance of A and call it like any old method, like so:

$a = new A();
$a->serialize();

It works as expected:

PHP version: 5.4.14

Serialized: {"a":1,"b":2}

Although this kind of defeats the purpose of using the Serializable interface.

Any thoughts?

Thanks.

Answer 1

What about http://php.net/manual/fr/jsonserializable.jsonserialize.php?

Like this :

$ cat test.php
<?php
class A implements JsonSerializable {
    private $a,
        $b,
        $c;

    public function __construct () {
        $this->a = 1;
        $this->b = 2;
        $this->c = 3;
    }

    public function jsonSerialize() {
        return [
            'a' => $this->a,
            'b' => $this->b
        ];
    }

}
echo json_encode(new A(), JSON_PRETTY_PRINT);
$ php test.php 
{
    "a": 1,
    "b": 2
}

But there is no unserialize function.

Do you really need to call serialize on it?