private void DanhSachTinh_Click_1(object sender, EventArgs e) { if (Tinhfrm == null || Tinhfrm.IsDisposed) { Tinhfrm = new frmTinh(); Tinhfrm.MdiParent = this; Tinhfrm.Show(); } else { Tinhfrm.Activate(); } }
private void ThemTinh_Click(object sender, EventArgs e) { frmTinh T = new frmTinh(); T.ShowDialog(); }