临时解决.net查询Mysql utf8mb4报给定关键字不在字典中

连接字符串的charset 仍然写utf8

查询DataTable时先设置一下编码可查询成功，不过需要两次查询

	try
        {
            DataTable dt = new DataTable();
            using (MySqlConnection conn = new MySqlConnection(Constants.MYSQL_STR))
            {
                conn.Open();
                MySqlCommand cmd2 = new MySqlCommand("set names utf8", conn);
                cmd2.ExecuteNonQuery();
                
                MySqlCommand cmd = conn.CreateCommand();
                cmd.CommandText = "select * from ypf_comment where cid = @source";
                cmd.CommandType = CommandType.Text;
                cmd.Parameters.Add(new MySqlParameter("@source", 2));
                MySqlDataAdapter sda = new MySqlDataAdapter(cmd);
                sda.Fill(dt);
                conn.Close();
            }
        }
        catch (MySqlException ex){ }