Question

Possible Duplicate:
recursive array_diff()?

I have a static multidimensional array which is always going to be in the same form. E.g. it will have the same keys & hierarchy.

I want to check a posted array to be in the same ‘form’ as this static array and if not error.

I have been trying various methods but they all seem to end up with a lot of if…else components and are rather messy.

Is there a succinct way to achieve this?

---

In response to an answer from dfsq:

$etalon = array(
    'name' => array(),
    'income' => array(
        'day'   => '',
        'month' => array(),
        'year'  => array()
    ),
    'message' => array(),
);

$test = array(
    'name' => array(),
    'income' => array(
        'day'   => '',
        'month' => array(),
        'year'  => array()
    ),
    'message' => array(),
);

// Tests
$diff = array_diff_key_recursive($etalon, $test);
var_dump(empty($diff));
print_r($diff);

And the results from that are

bool(false) 
Array ( [name] => 1 [income] => Array ( [month] => 1 [year] => 1 ) [message] => 1 ) 

Answer 1

Author needs a solution which would test if the structure of the arrays are the same. Next function will make a job.

/**
 * $a1 array your static array.
 * $a2 array array you want to test.
 * @return array difference between arrays. empty result means $a1 and $a2 has the same structure.
 */ 
function array_diff_key_recursive($a1, $a2)
{
    $r = array();

    foreach ($a1 as $k => $v)
    {
        if (is_array($v))
        {
            if (!isset($a2[$k]) || !is_array($a2[$k]))
            {
                $r[$k] = $a1[$k];
            }
            else
            {
                if ($diff = array_diff_key_recursive($a1[$k], $a2[$k]))
                {
                    $r[$k] = $diff;
                }
            }
        }
        else
        {
            if (!isset($a2[$k]) || is_array($a2[$k]))
            {
                $r[$k] = $v;
            }
        }
    }

    return $r;
}

And test it:

$etalon = array(
    'name' => '',
    'income' => array(
        'day'   => '',
        'month' => array(),
        'year'  => array()
    ),
    'message' => ''
);

$test = array(
    'name' => 'Tomas Brook',
    'income' => array(
        'day'   => 123,
        'month' => 123,
        'year'  => array()
    )
);

// Tests
$diff = array_diff_key_recursive($etalon, $test);
var_dump(empty($diff));
print_r($diff);

This will output:

bool(false)
Array
(
    [income] => Array
    (
        [month] => Array()

    )

    [message] => 
)

So checking for emptiness of $diff array will tell you if arrays have the same structure.

Note: if you need you can also test it in other direction to see if test array has some extra keys which are not present in original static array.