php merge 2 arrays

<?php
$array1 = array("color" => "red", 2, 4);
$array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4);
$result = array_merge($array1, $array2);
print_r($result);
?>
Array
(
    [color] => green
    [0] => 2
    [1] => 4
    [2] => a
    [3] => b
    [shape] => trapezoid
    [4] => 4
)

function custom_array_merge(&$array1, &$array2) {
    $result = Array();
    foreach ($array1 as $key_1 => &$value_1) {
        // if($value['name'])
        foreach ($array2 as $key_1 => $value_2) {
            if($value_1['name'] ==  $value_2['name']) {
                $result[] = array_merge($value_1,$value_2);
            }
        }

    }
    return $result;
}