private void btnKaydet_Click(object sender, EventArgs e)
        {
            KullaniciBL kbl = new KullaniciBL();

            foreach (DataRow item in dt.Rows)
            {
                Kullanici y = new Kullanici();
                if (item.RowState != DataRowState.Deleted)
                {
                    y.KullaniciAdi = item[1].ToString();
                }
                switch (item.RowState)
                {
                case DataRowState.Added:
                    kbl.Ekle(y);
                    break;

                case DataRowState.Deleted:
                    kbl.Sil(Convert.ToInt32(item[0, DataRowVersion.Original]));
                    break;

                case DataRowState.Modified:
                    y.KullaniciID = Convert.ToInt32(item[0]);
                    kbl.Guncelle(y);
                    break;

                default:
                    break;
                }
            }
        }
        private void btnKaydet_Click(object sender, EventArgs e)
        {
            KullaniciBL kbl = new KullaniciBL();
            Kullanici   kul = new Kullanici();

            kul.Ad           = txtKullaniciAd.Text.Trim();
            kul.Soyad        = txtSoyad.Text.Trim();
            kul.KullaniciAdi = txtKullaniciAdi.Text.Trim();
            kul.Sifre        = txtSifre.Text.Trim();
            if (BosKontrol() == true)
            {
                kbl.Ekle(kul);
                MessageBox.Show("Kayıt işlemi basarılı!");

                SayfayiYenile();
            }
            else if (BosKontrol() == false)
            {
            }
        }