PHP 5.3 accessing array key from object getter

Question

I have a Form object $form. One of its variables is a Field object which represents all fields and is an array (e.g $this->field['fieldname']). The getter is $form->fields().

To access a specific field method (to make it required or not for example) I use $form->fields()['fieldname'] which works on localhost with wamp but on the server throws this error:

Parse error: syntax error, unexpected '[' in (...)

I have PHP 5.3 on the server and because I reinstalled wamp and forgot to change it back to 5.3, wamp runs PHP 5.4. So I guess this is the reason for the error.

How can I access an object method, which returns an array, by the array key with PHP 5.3?

Use a temporary variable: $fields = $form->fields; echo $fields['fieldname']; — Jon
– Jon, Commented Jul 9, 2013 at 10:26
Just to explain what's going on here, this behaviour introduced in PHP 5.4 is called function array dereferencing. Documented here. — lonesomeday
– lonesomeday, Commented Jul 9, 2013 at 10:27
possible duplicate of 5.4 dereferencing to valid 5.3 array call — feeela
– feeela, Commented Jul 9, 2013 at 10:28
more details in the PHP documentation: php.net/manual/en/language.types.array.php#example-88 — feeela
– feeela, Commented Jul 9, 2013 at 10:29
possible duplicate of PHP syntax for dereferencing function result — cb0
– cb0, Commented Jul 9, 2013 at 10:32

Karo · Accepted Answer · 2013-07-09 10:27:40Z

3

Array dereferencing is possible as of PHP 5.4, not 5.3

PHP.net:

As of PHP 5.4 it is possible to array dereference the result of a function or method call directly. Before it was only possible using a temporary variable.

answered Jul 9, 2013 at 10:27

Karo

7444 silver badges7 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Davor Over a year ago

thanks. Unfortunately that means I cannot modify my $form object (since the $form->fields() has a lot of setters) because using temporary variables would only be useful for display.

Spudley · Accepted Answer · 2013-07-09 10:32:44Z

2

Array dereferencing as described in the question is a feature that was only added in PHP 5.4. PHP 5.3 cannot do this.

echo $form->fields()['fieldname']

So this code will work in PHP 5.4 and higher.

In order to make this work in PHP 5.3, you need to do one of the following:

Use a temporary variable:

$temp = $form->fields()
echo $temp['fieldname'];

Output the fields array as an object property rather than from a method:
ie this....
```
echo $form->fields['fieldname']
```
...is perfectly valid.
Or, of course, you could upgrade your server to PHP 5.4. Bear in mind that 5.3 will be declared end-of-life relatively soon, now that 5.5 has been released, so you'll be wanting to upgrade sooner or later anyway; maybe this is your cue to do? (and don't worry about it; the upgrade path from 5.3 to 5.4 is pretty easy; there's nothing really that will break, except things that were deprecated anyway)

answered Jul 9, 2013 at 10:32

Spudley

169k39 gold badges240 silver badges309 bronze badges

1 Comment

Davor Over a year ago

Cheers! I need to convince my host to give me 5.4, they only offer it for new accounts which is slightly ridiculous...

cb0 · Accepted Answer · 2013-07-09 10:31:58Z

1

As mentioned array dereferencing is only possible in 5.4 or greater. But you can save the object and later on access the fields:

$fields=$form->fields();
$value=$fields['fieldname']
...

AFAIK there is no other option.

answered Jul 9, 2013 at 10:31

cb0

8,6739 gold badges57 silver badges83 bronze badges

Collectives™ on Stack Overflow

PHP 5.3 accessing array key from object getter

3 Answers 3

1 Comment

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related