public void verigoster()
        {
            Mustericlass mc    = new Mustericlass();
            DataTable    table = mc.goster();

            MusteriListe.DataSource = table;
        }
        private void btn_guncelle_Click(object sender, EventArgs e)
        {
            Mustericlass mc = new Mustericlass();

            mc.musteriguncelle(txt_musteri.Text, txt_mustel.Text, txt_musadres.Text, Convert.ToInt32(txt_id.Text));
            verigoster();
            temizle();
        }
        private void btn_sil_Click(object sender, EventArgs e)
        {
            Mustericlass mc = new Mustericlass();

            mc.musterisil(Convert.ToInt32(txt_id.Text));
            verigoster();
            temizle();
        }
        private void btn_ekle_Click(object sender, EventArgs e)
        {
            Mustericlass mc = new Mustericlass();

            mc.musteriekle(txt_musteri.Text, txt_mustel.Text, txt_musadres.Text);
            verigoster();
            temizle();
        }