create new object from unserialize object in its constructor

Question

I have the testClass class and I want to create new object from unserialized object in its constructor. Is it possible? Something like this:

class testClass {
    public __constructor($id) {
        $queryData = DB::query(sql);
        $object = unserialize($queryData);
        $this = $object;
    }
}

In this way the rest of the code won't bother how the object is constructed:

$object = new testClass(3);

You can't.... $this already exists and is actively executing at the point where you're trying to metamorphose it; but you can take a factory approach — Mark Baker, Oct 19 '13 at 18:34
@MarkBaker, thanks, I'd appreciated if you provided an example as an answer, if possible — Max Koretskyi, Oct 19 '13 at 18:35
[What is a factory design pattern in php?](http://stackoverflow.com/questions/2083424/what-is-a-factory-design-pattern-in-php/) — Mark Baker, Oct 19 '13 at 18:38

score 0 · Answer 1 · answered Oct 19 '13 at 18:32

0

unserialize should give you the object already.

$object = new TestClass();
$queryData = serialize($object);
$object2 = unserialize($queryData);
// object2 is now a copy of object

answered Oct 19 '13 at 18:32

Halcyon

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Yes, but I want to make the object which is being constructed the object being unserialized – Max Koretskyi Oct 19 '13 at 18:33
1

You can't reassign `this`. You could try a factory function, but you'll end up reducing that to just `unserialize`. – Halcyon Oct 19 '13 at 18:34
Right, my aim is to not tell outside code how the object is constructed. Can you provide an example of factory as an example? – Max Koretskyi Oct 19 '13 at 18:36

score 0 · Answer 2 · answered Oct 19 '13 at 19:24

As Mark Baker and Frits van Campen suggested, I used factory:

public static function factory($idText = NULL, $rawText = NULL, $properties = NULL) {
    if ($idText === NULL) {
        return new Article($idText, $rawText, $properties);
    } else {
        $fetchedObject = self::fetchStoredObject($idText);
        if ($fetchedObject !== NULL) {
            return $fetchedObject;
        } else {
            throw new Exception('Article with ID ' . $idText . ' does not exist');
        }
    }
}

create new object from unserialize object in its constructor

2 Answers2