Ajax and Json post method

hi y'all,

I've got a small problem regarding ajax and json.

I'm using the .toArray(); to get the selected row into an array, and making a ajax post to convert it from Javascript to PHP.

(javascript)

var rowArray = dt.rows({selected: true}).data().toArray();
rowArray = JSON.stringify(rowArray);

  $.ajax({
                                type: 'POST',
                                url: 'customer.php',
                                data: {rowArray}
                            });

(php)

                     $json = json_decode($_POST['rowArray']);

                                    $phparra = array();

                                foreach ($json as $value)    {

                                    $phparra[] = $value;  
                                                                           }

I use the data afterwards to pass it into a php function.

I do not know where the exact problem is, but I think it's the format of the array or the decode part.

If I replace the rowArray with a simple array like this:

(javascript)

var cars = ["Saab", "Volvo", "BMW", "asdasd", "123123"]; 
cars = JSON.stringify(cars);

  $.ajax({
                                type: 'POST',
                                url: 'customer.php',
                                data: {cars}
                            });

(php)

                     $json = json_decode($_POST['cars']);

                                    $phparra = array();

                                foreach ($json as $value)    {

                                    $phparra[] = $value;  
                                                                           }

it works perfecly and passes the data to the php function and so on.

I've attached the Form data for both.

(cars)

(rowArray)

Hope someone can help!