combine associative arrays in PHP

Question

<?php
$arrayName1 = array(
    '0' => array('name' => 'steve' ,'age' =>51 ) , 
    '1' => array('name' => 'john' ,'age' =>48 ) , 
);

$arrayName2 = array(
    '0' => array('name' => 'Steve' ,'place' =>'downtown' ), 
    '1' => array('name' => 'John' ,'place' =>'New York' ), 
);

$output = array(
    '0' => array('name' => 'steve' ,'age' =>51, 'place' =>'downtown'  ), 
    '1' => array('name' => 'john' ,'age' =>48 ,'place' =>'New York' ), 
);

Looking forward to combine two arrays wrt the "name" key, and obtain the sample result as $output. array_merge() isn't working as expected.

Answer 1

If there is no guarantee that the same names will occur at the same indexes in the two arrays, you need to search for the matching name value in $arrayName2 and then merge the values from that entry into the value from $arrayName1:

$names2 = array_map('strtolower', array_column($arrayName2, 'name'));
$output = array();
foreach ($arrayName1 as $array) {
    $key = array_search($array['name'], $names2);
    if ($key !== false) {
        $output[] = $array + $arrayName2[$key];
    }
    else {
        $output[] = $array;
    }
}
print_r($output);

Output:

Array
(
    [0] => Array
        (
            [name] => steve
            [age] => 51
            [place] => downtown
        )
    [1] => Array
        (
            [name] => john
            [age] => 48
            [place] => New York
        )
)

Demo on 3v4l.org