Array value does not change

Question

I guess it is has something to do with ArrayAccess because $this and the objects in $this->products[$key] do implement ArrayAccess. However there is no magic __get or __set anywhere.

var_dump($this->products[$key]['selected_options'][$option_key]);
// Output: string(7) "Größe:S"

$this->products[$key]['selected_options'][$option_key] = "test";

var_dump($this->products[$key]['selected_options'][$option_key]);
// Output: string(7) "Größe:S"

Does someone have any idea what is wrong here?

Also note that this does work:

$this->products[$key]['selected_options'] = array($option_key => "test");
// Output: string(4) "test"

ArrayAccess for Products same for $this (Cart) but with $products instead of $data:

class Product implements ArrayAccess
{
    protected $data;

    /* **** ArrayAccess **** */
    public function offsetExists($offset) {
        return isset($this->data[$offset]);
    }

    public function offsetGet($offset) {
        return $this->data[$offset];
    }

    public function offsetSet($offset , $value) {
        $this->data[$offset] = $value;
    }

    public function offsetUnset($offset) {
        unset($this->data[$offset]);
    }
}

Yes. @OP: Did you test those lines exactly as presented here? No other code in between? — phant0m, Jan 26 '13 at 13:32
@Paul to make it more simple: assiging a string does not work. see update. — PiTheNumber, Jan 26 '13 at 13:33
Show the code of the ArrayAccess implementation. (I have removed your mentioning of the multi-dimensional array, that's misleading) — phant0m, Jan 26 '13 at 13:39

score 2 · Accepted Answer · edited Jun 20 '20 at 09:12

2

You need to return by reference inside offsetGet.

From the manual:

While direct modification triggers a call to ArrayAccess::offsetSet(), indirect modification triggers a call to ArrayAccess::offsetGet(). In that case, the implementation of ArrayAccess::offsetGet() must be able to return by reference, otherwise an E_NOTICE message is raised.

Note, however, that this only works with PHP >= 5.3.4

edited Jun 20 '20 at 09:12

Community

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answered Jan 26 '13 at 13:56

phant0m

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I added an & in `public function &offsetGet($offset) {` any now it works. Perfect, thanks a lot! – PiTheNumber Jan 26 '13 at 14:01

score 1 · Answer 2 · edited May 23 '17 at 10:34

1

You might be trying to change an immutable property.

How is $this->products defined? What is its visibility? You'll need to look into the scope of the current class and see whether properties can be overwritten after instantiation.

edited May 23 '17 at 10:34

Community

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answered Jan 26 '13 at 13:37

hohner

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I added the class definition. $this->products is an array of Products. – PiTheNumber Jan 26 '13 at 13:51

score 0 · Answer 3 · answered Jan 26 '13 at 13:36

Well i ran this:

// INPUT: string(7) "Größe:S"
$products = array();

$key = 1;
$option_key = 1;

$products[$key]['selected_options'][$option_key] = "badgers";

$products[$key]['selected_options'][$option_key] = "xxx";

var_dump($products[$key]['selected_options'][$option_key]);

And the output was:

string(3) "xxx"

So more code is needed i think?

Array value does not change

3 Answers3