public static FormKiemDuyetLenHang CreateInstance() { if (_singleton == null) { _singleton = new FormKiemDuyetLenHang(); } return(_singleton); }
private void btnKiemDuyet_Click(object sender, EventArgs e) { panelHover.Location = btnKiemDuyet.Location; HienThiForm(FormKiemDuyetLenHang.CreateInstance()); }