Ajax成功函数参数为空？

Question

Im getting an empty success function parameter back (lewa). But when I change 'lewa' to order (order.vnaam) it works. Could you point out what the problem is?

$(document).ready(function() {  
    $.ajax({
        type: 'POST',
        url: 'json-users.php',
        dataType: 'json',
        success: function(naam) {
            $.each(naam, function(i, item) {
                $('ul').append('<li>Voornaam: ' + item.voornaam + '<br>Achternaam: ' + item.achternaam + '</li>');
            });
        }
    }); //end get data db
}); //end document ready function

function upload() {

            var order = {
                vnaam: $('.voornaam').val(), 
                anaam: $('.achternaam').val(),
            };

            $.ajax({
                type: 'POST',
                url: 'posttest.php',
                /*dataType: 'json',*/
                data: order,
                success: function( lewa ) {
                        //When action is a success
                        $('ul').append('<li>Voornaam: ' + lewa.vnaam + '<br>Achternaam: ' + lewa.anaam + '</li>');
                        console.log(lewa);
                        console.log(order);
                },
                error: function() {
                        //When action is a failure
                        alert('error running function');
                }
            });

}

The following code is posttest.php

$voornaam = mysqli_real_escape_string($connect, $_POST["vnaam"]);
$achternaam = mysqli_real_escape_string($connect, $_POST["anaam"]);


$sql = "INSERT INTO users (voornaam, achternaam) VALUES ('".$voornaam."', '".$achternaam."')";

mysqli_query($connect, $sql);

The following code is json-users.php

$array_user = array();

    while ( $data = mysqli_fetch_assoc($result) ) {
        $array_user[] = $data;
    }

    echo json_encode($array_user);

Answer 1

Didnt return anything from posttest.php