Access PHP array element with a function?

Question

I'm working on a program that uses PHP's internal array pointers to iterate along a multidimensional array. I need to get an element from the current row, and I've been doing it like so:

$arr[key($arr)]['item']

However, I'd much prefer to use something like:

current($arr)['item'] // invalid syntax

I'm hoping there's a function out there that I've missed in my scan of the documentation that would enable me to access the element like so:

getvalue(current($arr), 'item')

or

current($arr)->getvalue('item')

Any suggestions?

You have already found the best solution: $arr[key($arr)]['item'] — Bill Karwin
– Bill Karwin, Commented Dec 28, 2008 at 20:27
The getvalue approach would be useful even of single-dimmensional arrays too. It would allow to workaroung the ≤5.3 syntax limitations and allowing to access an element from an array, say returned by a function call, directly within one statement. I’m missing such internal function. — Glutexo
– Glutexo, Commented May 26, 2015 at 5:28

Adam Wright · Accepted Answer · 2013-04-28 14:29:14Z

12

I very much doubt there is such a function, but it's trivial to write

function getvalue($array, $key)
{
  return $array[$key];
}

Edit: As of PHP 5.4, you can index array elements directly from function expressions, current($arr)['item'].

edited Apr 28, 2013 at 14:29

answered Dec 28, 2008 at 19:05

Adam Wright

49.5k12 gold badges134 silver badges153 bronze badges

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

1 Comment

Kyle Cronin Over a year ago

I think this is probably what I'll end up doing. If you are correct that there is no such function, it's a pretty bad oversight.

user42092 · Accepted Answer · 2008-12-28 19:13:11Z

1

Have you tried using one of the iterator classes yet? There might be something in there that does exactly what you want. If not, you can likely get what you want by extending the ArrayObject class.

answered Dec 28, 2008 at 19:13

user42092

1 Comment

Kyle Cronin Over a year ago

Just looked at those - it looks like that's just an object oriented way to iterate through the array. The ArrayIterator::current returns the current item, much in the same way the current() function does, which isn't really the problem I was having.

Alix Axel · Accepted Answer · 2009-04-29 04:32:12Z

This function might be a bit lenghty but I use it all the time, specially in scenarious like:

if (array_key_exists('user', $_SESSION) === true)
{
    if (array_key_exists('level', $_SESSION['user']) === true)
    {
        $value = $_SESSION['user']['level'];
    }

    else
    {
        $value = 'DEFAULT VALUE IF NOT EXISTS';
    }
}

else
{
    $value = 'DEFAULT VALUE IF NOT EXISTS';
}

Turns to this:

Value($_SESSION, array('user', 'level'), 'DEFAULT VALUE IF NOT EXISTS');

Here is the function:

function Value($array, $key = 0, $default = false)
{
    if (is_array($array) === true)
    {
        if (is_array($key) === true)
        {
            foreach ($key as $value)
            {
                if (array_key_exists($value, $array) === true)
                {
                    $array = $array[$value];
                }

                else
                {
                    return $default;
                }
            }

            return $array;
        }

        else if (array_key_exists($key, $array) === true)
        {
            return $array[$key];
        }
    }

    return $default;
}

PS: You can also use unidimensional arrays, like this:

Value($_SERVER, 'REQUEST_METHOD', 'DEFAULT VALUE IF NOT EXISTS');

chelmertz · Accepted Answer · 2008-12-29 16:59:48Z

-1

If this does not work, how is your multidimensional array composed? A var_dump() might help.

$subkey = 'B';
$arr = array(
    $subkey => array(
        'AB' => 'A1',
        'AC' => 'A2'
    )
);


echo current($arr[$subkey]);
next($arr[$subkey]);
echo current($arr[$subkey]);

answered Dec 29, 2008 at 16:59

chelmertz

20.6k5 gold badges42 silver badges46 bronze badges

2 Comments

Kyle Cronin Over a year ago

The iteration I'm performing is really only along the primary array. I said "multidimensional" because the corresponding elements of the main array are themselves arrays, but I don't want to iterate over them - I just want to conveniently access them.

chelmertz Over a year ago

How about treating $arr[$subkey] as an array, or $new_arr = array_values($arr[$subkey])? Footnote: what differs between your requested current($arr)['item'] and current($arr['item'])?

Gerrit · Accepted Answer · 2008-12-29 17:13:45Z

-1

I often use

foreach ($arr as $key=>$val) {
   $val['item'] /*$val is the value of the array*/
   $key         /*$key is the key used */
}

instead of

next($arr)/current($arr)

answered Dec 29, 2008 at 17:13

Gerrit

1,6095 gold badges17 silver badges23 bronze badges

1 Comment

Kyle Cronin Over a year ago

I use that too - for the sake of the question I eliminated the fact that I'm actually going down two sorted arrays looking for differences, and I' m pretty sure foreach doesn't support that kind of access, but I could be wrong. Anyways, thanks for your reply. :)

Collectives™ on Stack Overflow

Access PHP array element with a function?

5 Answers 5

1 Comment

1 Comment

Comments

2 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

5 Answers 5

1 Comment

1 Comment

Comments

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related