How to check if a multi-dimensional array only contains empty values?

Question

I looked around and can't quite find the answer for this, so I'm wondering if I contain an array such as this..

$array['foo']['bar'][1] = '';
$array['foo']['bar'][2] = '';
$array['foo']['bar'][3] = '';
$array['foo']['bar'][4] = '';

How can I check if all the values are empty? I tried doing the following:

if (empty($array['foo']['bar'])) {
    // Array empty
}

But as expected that didn't work.

How can I do this?

Answer 1

If you wanted to check to see if all of the values where populated you can use

 if(call_user_func_array("isset", $array['foo']['bar']))

For what you want to do though you could use array reduce with a closure

 if(array_reduce($array, function(&$res, $a){if ($a) $res = true;}))

Note this will only work in php 5.3+

Answer 2

$array['foo']['bar'] isn't empty because it's actually array(1=>'',2=>'',3=>'',4=>'').

You would need to do a foreach loop on it to check if it is indeed all empty.

$arr_empty = true;
foreach ($array['foo']['bar'] as $arr) {
    if (!empty($arr)) {
        $arr_empty = false;
    }
}
//$arr_empty is now true or false based on $array['foo']['bar']

Answer 3

A short alternative would be:

if (empty(implode($array['foo']['bar']))) {
  // is empty
}

Note that some single values may be considered as empty. See empty().