protected void Button1_Click(object sender, EventArgs e)
        {
            EntityOgrenci ent = new EntityOgrenci();


            ent.Ad       = TxtAd.Text;
            ent.Soyad    = TxtSoyad.Text;
            ent.Numara   = TxtNumara.Text;
            ent.Sifre    = TxtSifre.Text;
            ent.Fotograf = TxtFoto.Text;
            ent.Id       = Convert.ToInt32(TxtId.Text);
            BLLOgrenci.OgrenciGuncelleBll(ent);

            Response.Redirect("OgrenciListesi.aspx");
        }