[HttpPost]
        public ActionResult Iletisim(FormModel model)
        {
            MailMessage _mm = new MailMessage();



            _mm.SubjectEncoding = Encoding.Default;
            _mm.Subject = model.AdiSoyadi;
            _mm.BodyEncoding = Encoding.Default;
            _mm.Body = model.Mesaj;

            _mm.From = new MailAddress(ConfigurationManager.AppSettings["emailAccount"]);
            _mm.To.Add("mil@gmail.com");


            SmtpClient _smtpClient = new SmtpClient();
            _smtpClient.Host = ConfigurationManager.AppSettings["emailHost"];
            _smtpClient.Port = int.Parse(ConfigurationManager.AppSettings["emailPort"]);
            _smtpClient.Credentials = new NetworkCredential(ConfigurationManager.AppSettings["emailAccount"], ConfigurationManager.AppSettings["emailPassword"]);
            _smtpClient.EnableSsl = bool.Parse(ConfigurationManager.AppSettings["emailSLLEnable"]);

            _smtpClient.Send(_mm);

            TempData["Basarili"] = " Teşekürler en kısa zamanda tafarınıza dönüş yapılacaktır.";

            return RedirectToAction("Iletisim");



        }

@using (Html.BeginForm("Iletisim", "ContactUs", FormMethod.Post, new { @class = "well form-horizontal" }))
            {
                <fieldset>
                    @Html.ValidationSummary(true, "", new { @class = "text-danger" })
                    <!-- Form Name -->
                    <legend class="col-form-label-lg">İletişim Formu!</legend>
                    <!-- Text input-->
                    <div class="form-group">
                        <label class="col-6 col-form-label">Adı Soyadı :</label>
                        <div class="col-6 col-form-label">
                            <div class="input-group">
                                <span class="text-center"><i class="fa fa-user fa-2x"></i></span>
                                @Html.TextBoxFor(model => model.AdiSoyadi, new { @class = "form-control", placeholder = "Adınız Soyadınız" })
                            </div>
                            @Html.ValidationMessageFor(model => model.AdiSoyadi, "", new { @class = "text-danger" })
                        </div>
                    </div>
                    <!-- Text input-->
                    <div class="form-group">
                        <label class="col-6 col-form-label">E-Posta :</label>
                        <div class="col-6 col-form-label">
                            <div class="input-group">
                                <span class="text-center"><i class="fa fa-envelope fa-2x"></i></span>
                                @Html.TextBoxFor(model => model.Email, new { @class = "form-control", placeholder = "Email Adresiniz" })
                            </div>
                            @Html.ValidationMessageFor(model => model.Email, "", new { @class = "text-danger" })
                        </div>
                    </div>
                    <!-- Text area -->
                    <div class="form-group">
                        <label class="col-md-6 col-form-label">Mesajınız :</label>
                        <div class="col-md-6 col-form-label">
                            <div class="input-group">
                                <span class="text-center"><i class="fa fa-pencil-square-o fa-2x"></i></span>
                                @Html.TextAreaFor(model => model.Mesaj, new { @class = "form-control", placeholder = "Mesajınız " })

                            </div>
                            @Html.ValidationMessageFor(model => model.Mesaj, "", new { @class = "text-danger" })
                        </div>
                    </div>
                    @if (TempData["Basarili"] != null)
                    {
                        <!-- Success message -->
                        <div class="alert gonder" role="alert" id="success_message">
                            Gönderildi <span class="fa fa-thumbs-o-up fa-2x fa-fw"></span>@TempData["Basarili"]
                        </div>
                    }
                    <!-- Button -->
                    <div class="form-group">
                        <label class="col-md-6 col-form-label"></label>
                        <div class="col-md-6">
                            <button type="submit" class="btn gonder">Gönder <span class="fa fa-send-o fa-2x fa-fw"></span></button>
                        </div>
                    </div>
                </fieldset>
            }

 
  string veri; 
      DataTable dt = new DataTable(); 
      protected void Page_Load(object sender, EventArgs e) 
      { 
          SqlConnection conn = new SqlConnection("connectionstring"); 
          SqlDataAdapter da = new SqlDataAdapter("select * from Kategoriler", conn); 
           
          da.Fill(dt); 
          kategori(TreeView1.Nodes[0],getrows("0")); 
          //ürünler kısmı 
          DataSet ds = new DataSet(); 
          da.Fill(ds, "datst"); 
          SqlCommand com = new SqlCommand("select * from urunler",conn); 
          conn.Open(); 
          SqlDataReader rd = com.ExecuteReader(); 
          DataList1.DataSource = rd; 
          DataList1.DataBind(); 
           
           
           
      } 
      DataRowCollection getrows(string id) 
      { 
      DataView dw = new DataView(dt); 
      dw.RowFilter = "AltKategoriID="+id; 
      return dw.ToTable().Rows; 
      } 
   
       
      void kategori(TreeNode node, DataRowCollection col) 
      { 
          foreach (DataRow row in col) 
          { 
              TreeNode tn = new TreeNode(row[1].ToString()); 
              node.ChildNodes.Add(tn); 
              kategori(tn, getrows(row[0].ToString())); 
              tn.NavigateUrl = "Default.aspx?CatID=" + tn.Text; 
               
          } 
      } 
      protected void TreeView1_SelectedNodeChanged(object sender, EventArgs e) 
      { 
     
   
      }