public void EditClass(mst_class mst)
        {
            try
            {
                using (MySqlConnection con = new MySqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ToString()))
                {
                    string query = @"UPDATE mst_class 
                                    SET
                                        class_name = @class_name
                                    WHERE
                                        class_id = @class_id
                                        AND session = (SELECT
                                                session
                                            FROM
                                                mst_session
                                            WHERE
                                                session_active = 'Y')";

                    con.Execute(query, mst);
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        public void AddClass(mst_class mst)
        {
            try
            {
                using (MySqlConnection con = new MySqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ToString()))
                {
                    mst_sessionMain session = new mst_sessionMain();
                    string          sess    = session.findActive_Session();

                    string query = "INSERT INTO mst_class (session,class_id,class_name) VALUES (@session,@class_id,@class_name)";

                    string maxid = @"SELECT 
                                        IFNULL(MAX(class_id), 0) + 1
                                    FROM
                                        mst_class
                                    WHERE
                                        session = (SELECT
                                                session
                                            FROM
                                                mst_session
                                            WHERE
                                                session_active = 'Y')";

                    //                var id = con.Query<mst_section>(maxid).ToString().Trim();

                    int id = con.ExecuteScalar <int>(maxid);


                    mst.class_id   = id;
                    mst.class_name = mst.class_name.Trim();

                    con.Execute(query, new
                    {
                        session = sess,
                        mst.class_id,
                        mst.class_name
                    });
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }