Удалить страницу ответа из AJAX

Question

Я создал страницу asp. net, включив функцию почты на этой странице. Страница имеет контактную форму. Отправляет почту после заполнения формы. Почта идет, но откройте страницу с ответом. Здесь откроется страница с ответом, и появится только мой ответ. Я использовал AJAX, но я не смог предотвратить открытие страницы. Как я могу это сделать?

HTML:

<script type=text/javascript>
    $("input[name=buttonsubmit]").click(function () {
        $.ajax({
            type: "POST",
            url: "Default.aspx",
            data: form,
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (response) {
                if (response.toString == 1) {
                    alert("form success");
                } 
            }
        });
    });
</script>
<form action="Default.aspx" method="post">
                    <div class="form-group row">
                        <div class="col-12">
                            <input type="text" name="namesurname" class="form-control form-control-lg" style="border:none; border-bottom:solid; border-bottom-color:#00195A" placeholder="Ad Soyad">
                        </div>
                    </div>
                    <div class="form-group row">
                        <div class="col-12">
                            <input type="email" name="emailaddress" class="form-control form-control-lg" style="border:none; border-bottom:solid; border-bottom-color:#00195A" placeholder="E-mail">
                        </div>
                    </div>
                    <div class="form-group row">
                        <div class="col-12">
                            <input type="tel" name="phonenumber" class="form-control form-control-lg" style="border:none; border-bottom:solid; border-bottom-color:#00195A" placeholder="Telefon">
                        </div>
                    </div>
                    <div class="form-group row">
                        <div class="col-12">
                            <textarea type="text" name="messagearea" class="form-control form-control-lg" style="border:none; border-bottom:solid; border-bottom-color:#00195A" placeholder="Mesajınız"></textarea>
                        </div>
                    </div>
                    <div class="form-group row">
                        <div class="col-12 button">
                            <input type="submit" name="buttonsubmit" class="form-control form-control-lg" style="border:solid; color:#00195A" value="Gönder">
                        </div>
                    </div>
                </form>

Default.aspx:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

Default.aspx.cs:

    protected void Page_Load(object sender, EventArgs e)
{
    try
    {
        string adSoyad = Request.Form["namesurname"];
        string epostaAdresi = Request.Form["emailaddress"];
        string tel = Request.Form["phonenumber"];
        string mesaji = Request.Form["messagearea"];

        string ipAdresi = ""; //gönderenin IP adresini alıyoruz (localde 127.0.0.1 yada ::1 şeklinde gözükür)
        if (HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
            ipAdresi = HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString();
        else if (HttpContext.Current.Request.UserHostAddress.Length != 0)
            ipAdresi = HttpContext.Current.Request.UserHostAddress;

        string mesajIcerik = "";//mesaj içeriği HTML ile biçimlendirilebilir
        mesajIcerik += "<b>İletişim Formundan Gelen Mesaj</b> / " + DateTime.Now.ToString() + " / " + ipAdresi + "<br/>";
        mesajIcerik += "<b>Adı Soyadı: </b>" + adSoyad + "<br/>";
        mesajIcerik += "<b>E-posta: </b>" + epostaAdresi + "<br/>";
        mesajIcerik += "<b>Telefon: </b>" + tel + "<br/>";
        mesajIcerik += "<b>İleti: </b>" + mesaji;

        MailMessage yeniMesaj = new MailMessage();
        yeniMesaj.IsBodyHtml = true;
        yeniMesaj.To.Add("***@gmail.com");//buraya alıcı mail adresiniz gelecek
        yeniMesaj.From = new MailAddress("***@gmail.com", "***", System.Text.Encoding.UTF8); // buraya gönderen mail adresiniz ve görünecek ismi gelecek
        yeniMesaj.Subject = "Yeni Mesaj: " + adSoyad; //buraya mail konusunda görünecek kısım gelecek
        yeniMesaj.Body = mesajIcerik;

        SmtpClient gonder = new SmtpClient();
        gonder.Credentials = new NetworkCredential("***@gmail.com", "***");//buraya gönderen mail adresiniz ve şifreniz gelecek
        gonder.Port = 587; //gmail için varsayılan SMTP port
        gonder.Host = "smtp.gmail.com"; //gmail için smtp adresi
        gonder.EnableSsl = true;
        gonder.Send(yeniMesaj);
        Response.Write("1");
        //Response.End();
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);
        //Response.End();
    }
}