public class Database : IDisposable
{
    MySqlConnection conn

    public Database()
    {
        conn = new MySqlConnection(connectionString);
    }

        public DataTable GetDataTable(string sql, List<MySqlParameter> args)
        {
            DataTable dt = new DataTable();
            MySqlDataAdapter da = new MySqlDataAdapter();

            using (MySqlCommand cmd = new MySqlCommand(sql, conn))
            {
                if (args.Count > 0)
                {
                    cmd.Parameters.AddRange(args.ToArray());
                }

                da.SelectCommand = cmd;
                da.Fill(dt);
            }

            if (dt.Rows.Count > 0)
            {
                return dt;
            }
            else
            {
                return null;
            }
        }
}