csharp 计算返回查询的行数

Posted 2021-05-12

        public static int count_selected_row(string conString, string query)
        {
            var NumRows =0;
            try
            {
                using (MySqlConnection conn = new MySqlConnection(conString))
                {
                    using (MySqlCommand cmd = new MySqlCommand(query, conn))
                    {
                        conn.Open();
                        NumRows = Convert.ToInt16( cmd.ExecuteScalar());
                        return NumRows;
                    }
                }
            }
            catch (MySqlException ex1)
            {
                MessageBox.Show("Db_util class \n  count_selected_row  \n MySqlException \n" + ex1);
                return -1;
            }
            catch (Exception ex)
            {
                MessageBox.Show("Db_util class count_selected_row " + ex);
                return -1;
            }
        }