What is the best approach to converting a multidimensional array into a one-dimensional array in PHP?

When converting a multidimensional array into a one-dimensional array in PHP, the best approach is to use a recursive function to flatten the array. This function will iterate through each element of the array, checking if the element is an array itself. If it is, the function will recursively call itself to flatten that sub-array. Finally, the function will merge all the elements into a single one-dimensional array.

function flattenArray($array) {
    $result = [];
    foreach ($array as $element) {
        if (is_array($element)) {
            $result = array_merge($result, flattenArray($element));
        } else {
            $result[] = $element;
        }
    }
    return $result;
}

$multiArray = [[1, 2, [3]], 4, [5, 6]];
$oneDimensionalArray = flattenArray($multiArray);

print_r($oneDimensionalArray);