mysqli_prepare不能正常工作

Question

我想在我的表格中插入一些记录，为此我使用mysqli_prepare，bind_param和execute。

在element inspection中，他在500 internal server error中提供params，他会提供我需要的所有数据。

我希望你们能帮助我，这是我的代码：

PHP

<form id="addFolder">
    <div class="form-group col-md-6">
        <label for="folderName">Map naam</label>
        <input type="text" class="form-control" id="folderName" placeholder="Map naam">
    </div>
    <div class="form-group col-md-6">
        <label for="selectRootFolder">Selecteer root map</label>
        <select class="form-control" id="selectRootFolder">
            <?php
            getRootFolders();
            ?>
        </select>
    </div>
    <div class="form-group col-md-6">
        <label for="selectIcon">Selecteer icon <span class="fa fa-question-circle" id="fa-ask"></span></label>
        <input type="text" class="form-control" id="selectIcon" placeholder="fa fa-icon">
    </div>
    <br><br><br>
    <div class="form-group col-md-4">
        <div class="checkbox">
            <label>
                <input type="checkbox" id="isRootMap"> Is root map
            </label>
        </div>
        <div class="checkbox">
            <label>
                <input type="checkbox" id="active"> Actief
            </label>
        </div>
    </div>
    <input type="submit" class="btn btn-info" value="Voeg toe" style="float:right; margin-top: 4%;">
</form>

的jQuery

$("#addFolder").on("submit", function(e) {
    e.preventDefault();

    var folderName = $("#folderName").val();
    var rootId = $("#selectRootFolder").find("option:selected").data("id");
    var isRoot = $("#isRootMap").is(":checked");
    var icon = $("#selectIcon").val();
    var active = $("#active").is(":checked");

    var array = [folderName, rootId, isRoot, icon, active];

    $.ajax({
        method: "POST",
        url: "../admin/handlers/addFolderHandler.php",
        data: { data: array }
    }).done(function(data) {
        if (data == true)
        {
            window.location.href = "index.php";
        }
    });
});

处理程序

<?php
$gegevens = $_POST['data'];

$folderName = $gegevens[0];
$rootId = ($gegevens[3] == true) ? NULL : $gegevens[1];
$isRoot = ($gegevens[3] == true) ? 1 : 0;
$icon = ($gegevens[3] == true) ? $gegevens[4] : "";
$active = ($gegevens[5] == true) ? "1" : "0";

if (addNewFolder($rootId, $isRoot, $folderName, $icon, $active))
{
    echo true;
}
else
{
    echo false;
}
?>

功能

function addNewFolder($rootId, $isRoot, $folderName, $icon, $active)
{
    global $con;

    $query = mysqli_prepare($con, "INSERT INTO folders (parent_id, is_root, `name`, icon, active) VALUES (?, ?, ?, ?, ?)");
    $query->bind_param('ddssi', $rootId, $isRoot, $folderName, $icon, $active);

    if ($query->execute())
    {
        return true;
    }
    else
    {
        return false;
    }
}