private void btnCancelInput_Click(object sender, EventArgs e) { try { DialogResult option; option = MessageBox.Show("Do you really want to delete?", "SysBusiness", MessageBoxButtons.OKCancel, MessageBoxIcon.Question); if (option == DialogResult.OK) { string Code; string resp = ""; foreach (DataGridViewRow row in dataList.Rows) { if (Convert.ToBoolean(row.Cells[0].Value)) { Code = Convert.ToString(row.Cells[1].Value); resp = BSale.Delete(Convert.ToInt32(Code)); if (resp.Equals("OK")) { this.MessageOk("Success deleted"); } else { this.MessageError(resp); } } } this.Show(); } } catch (Exception ex) { MessageBox.Show(ex.Message + ex.StackTrace); } }