How to correctly pass strings to a function?

Question

WordPress

Hello, please help me understand.

There are two forms (.user-create-form and .user-edit-form) and when saving data (on submit), I want to display messages in a block (#user-action-message). For example, when creating a user, the message "A new user has been created", and when editing, the message "User data has been updated". Tried to use the following code but it throws an error. I think I am incorrectly passing the string to the saveForm function.

ERROR:

TypeError: Argument 1 of FormData.constructor does not implement interface HTMLFormElement.

JS:

var saveForm = function (success_message) {
        var form = $(this);
        var formData = new FormData(form[0]);
        $.ajax({
            url: form.attr("action"),
            data: formData,
            type: form.attr("method"),
            dataType: 'json',
            success: function (data) {
                if (data.form_is_valid) {
                    $("#users").html(data.html_users);
                    $("#user-action-message").html(success_message); <-- ПОКАЗАТЬ сообщения здесь
                    $("#modal-lg").modal("hide");
                }
                else {
                    $("#user-modal .modal-content").html(data.html_form);
                }
            }
        });
        return false;
    };

$("#user-modal").on("submit", ".user-create-form", saveForm("Новый пользователь успешно создан!"));
$("#user-modal").on("submit", ".user-edit-form", saveForm("Данные пользователя успешно сохранены!"));

Answer 1

it's called "cloudflare cache"

Answer 2

Everything is ok with the line.
Check what exactly you are passing in FormData.
Something like this: https://jsfiddle.net/z5jmmdpa/

Answer 3

The problem is somewhere in . Print to the console up to new FormData form[0]