Using array_intersect on a multi-dimensional array

Question

I have two arrays that both look like this:

Array
(
    [0] => Array
        (
            [name] => STRING
            [value] => STRING
        )

    [1] => Array
        (
            [name] => STRING
            [value] => STRING
        )

    [2] => Array
        (
            [name] => STRING
            [value] => STRING
        )
)

and I would like to be able to replicate array_intersect by comparing the ID of the sub arrays within the two master arrays. So far, I haven't been successful in my attempts. :(

Doing a custom comparison, you'll need to use `array_uintersect()` http://php.net/array_uintersect, which uses a user-defined comparison function. — Wiseguy, Apr 13 '11 at 17:47
Despite all of the upvotes on this old post, your question does not contain a good, clear [mcve]. — mickmackusa, Jan 24 '22 at 22:38
[Compare two 2D arrays & get intersection and differences](https://stackoverflow.com/q/37564953/2943403) — mickmackusa, Feb 24 '22 at 05:03

score 57 · Accepted Answer · answered Apr 13 '11 at 17:59

Use array_uintersect() to use a custom comparison function, like this:

$arr1 = array(
           array('name' => 'asdfjkl;', 'value' => 'foo'),
           array('name' => 'qwerty', 'value' => 'bar'),
           array('name' => 'uiop', 'value' => 'baz'),
        );

$arr2 = array(
           array('name' => 'zxcv', 'value' => 'stuff'),
           array('name' => 'asdfjkl;', 'value' => 'foo'),
           array('name' => '12345', 'value' => 'junk'),
           array('name' => 'uiop', 'value' => 'baz'),
        );

$intersect = array_uintersect($arr1, $arr2, 'compareDeepValue');
print_r($intersect);

function compareDeepValue($val1, $val2)
{
   return strcmp($val1['value'], $val2['value']);
}

which yields, as you would hope:

Array
(
    [0] => Array
        (
            [name] => asdfjkl;
            [value] => foo
        )

    [2] => Array
        (
            [name] => uiop
            [value] => baz
        )

)

How could you modify this to make sure all columns match, not just 'value'? — bafromca, Jan 20 '16 at 08:41
@bafromca I think return strcmp(serialize($val1), serialize($val2)); might work — ChrisS, Jun 15 '16 at 13:49
better use a recursive funktion like: `function compare_arrays($a, $b) { if (is_array($a) && is_array($b)) { $diff = array_udiff($a, $b, 'compare_arrays'); return empty($diff) ? 0 : 1; } return ($a < $b) ? -1 : 1; } $result = array_uintersect($a, $b, 'compare_arrays');` — rubo77, Apr 08 '23 at 17:26

score 3 · Answer 2 · edited Dec 21 '15 at 14:07

3

function compareDeepValue($val1, $val2)
{
   return strcmp($val1['value'], $val2['value']);
}

Be sure that val2 key is existing in val1 array, because the function is ordering array first. Very strange.

edited Dec 21 '15 at 14:07

smottt

3,272
11
37
44

answered Dec 21 '15 at 13:50

ScreamZ

39
1

score 3 · Answer 3 · answered May 08 '19 at 06:21

you can use embedded function with array_uintersect php function. ex:

$intersectNames = array_uintersect($arr1, $arr2, function ($val1, $val2){
    return strcmp($val1['name'], $val2['name']);
    });

$intersectValues = array_uintersect($arr1, $arr2, function ($val1, $val2){
    return strcmp($val1['value'], $val2['value']);
    });

print_r('namesIntersected' => $intersectNames, 'valuesIntersected' => $intersectValues)

Using array_intersect on a multi-dimensional array

3 Answers3

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