private void btnThemNCC_Click(object sender, EventArgs e) { txtTenNCC.Clear(); txtDiaChi.Clear(); txtSDT.Clear(); txtTenNCC.Enabled = true; cboMaLoai.Enabled = true; txtTenNCC.Enabled = true; txtDiaChi.Enabled = true; txtSDT.Enabled = true; btnLuuNCC.Enabled = true; btnXoaNCC.Enabled = false; btnSuaNCC.Enabled = false; if (dgvNhaCC.RowCount <= 0) { txtMaNCC.Text = "NCC01"; } else { txtMaNCC.Text = ncc_bll.getMaNhaCungCap(); } add = true; update = false; }