SqlConnection conn = new SqlConnection("server=localhost;Initial catalog =LIS;uid=sa;password=;");
conn.Open();
SqlDataAdapter adapter = new SqlDataAdapter("SELECT XM FROM BRXX WHERE ID=" + n, conn);
SqlCommandBuilder builder = new SqlCommandBuilder(adapter);
SqlConnection conn = new SqlConnection("server=localhost;Initial catalog =LIS;uid=sa;password=;");
SqlDataAdapter adapter = new SqlDataAdapter("SELECT XM FROM BRXX WHERE ID=" + n, conn);
DataSet ds = new DataSet();
adapter.Fill(ds,"BRXX");
string xm = ds.Tables["BRXX"].Rows[5]["XM"].ToString();