How to convert all keys in a multi-dimenional array to snake_case?

Question

I am trying to convert the keys of a multi-dimensional array from CamelCase to snake_case, with the added complication that some keys have an exclamation mark that I\'d like rem

Answer 1

superficieAll_1 = 80;
$maison->addressBook->longitudeAmi = 2;
$maison->addressBook->latitude = 4;

$returnedArray = transformation($maison);
print_r($returnedArray);

function transformation($obj){
    //object to array
    $array = json_decode(json_encode((array) $obj),true);
    //now transform all array keys
    return transformKeys($array);
}    

function transformKeys($array)
{
    foreach ($array as $key => $value){
        // echo "$key 
";
        unset($array[$key]);
        $transformedKey = strtolower(preg_replace('/([a-z])([A-Z])/', '$1_$2', ltrim($key, '!')));
        $array[$transformedKey] = $value;  
        // echo "$transformedKey update 
";
        if (is_array($value)) {
            $array[$transformedKey] = transformKeys($value);
        }
    }
    return $array;
}