MySQL数据库操作类请教

[v从自行车的]

    /// <summary>
    /// 数据库操作
    /// </summary>
    public class DatebaseHelper
    {
        #region 数据库连接字符串
        public static readonly string DBConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings["YMC"].ToString();
        #endregion

        /// <summary>
        /// Command预处理
        /// </summary>
        /// <param name="conn">MySqlConnection对象</param>
        /// <param name="trans">MySqlTransaction对象，可为null</param>
        /// <param name="cmd">MySqlCommand对象</param>
        /// <param name="cmdType">CommandType，存储过程或命令行</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组，可为null</param>
        private static void PrepareCommand(MySqlConnection conn, MySqlTransaction trans, MySqlCommand cmd, CommandType cmdType, string cmdText, MySqlParameter[] cmdParms)
        {
            if (conn.State != ConnectionState.Open)
                conn.Open();
            cmd.Connection = conn;
            cmd.CommandText = cmdText;
            if (trans != null)
                cmd.Transaction = trans;
            cmd.CommandType = cmdType;
            if (cmdParms != null)
            {
                foreach (MySqlParameter parm in cmdParms)
                    cmd.Parameters.Add(parm);
            }

        }
        
        /// <summary>
        /// 执行命令
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">命令类型（存储过程或SQL语句）</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组</param>
        /// <returns>返回受引响的记录行数</returns>
        public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            using (MySqlConnection conn = new MySqlConnection(connectionString))
            {
                PrepareCommand(conn, null, cmd, cmdType, cmdText, cmdParms);
                int val = cmd.ExecuteNonQuery();
                cmd.Parameters.Clear();
                return val;
            }
        }

        /// <summary>
        /// 执行命令
        /// </summary>
        /// <param name="conn">Connection对象</param>
        /// <param name="cmdType">命令类型（存储过程或SQL语句）</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组</param>
        /// <returns>返回受引响的记录行数</returns>
        public static int ExecuteNonQuery(MySqlConnection conn, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            PrepareCommand(conn, null, cmd, cmdType, cmdText, cmdParms);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }

        /// <summary>
        /// 执行事务
        /// </summary>
        /// <param name="trans">MySqlTransaction对象</param>
        /// <param name="cmdType">命令类型（存储过程或SQL语句）</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组</param>
        /// <returns>返回受引响的记录行数</returns>
        public static int ExecuteNonQuery(MySqlTransaction trans, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            PrepareCommand(trans.Connection, trans, cmd, cmdType, cmdText, cmdParms);
            int val = cmd.ExecuteNonQuery();
            cmd.Parameters.Clear();
            return val;
        }

        /// <summary>
        /// 执行命令，返回第一行第一列的值
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">命令类型（存储过程或SQL语句）</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组</param>
        /// <returns>返回Object对象</returns>
        public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            using (MySqlConnection connection = new MySqlConnection(connectionString))
            {
                PrepareCommand(connection, null, cmd, cmdType, cmdText, cmdParms);
                object val = cmd.ExecuteScalar();
                cmd.Parameters.Clear();
                return val;
            }

        }

        /// <summary>
        /// 执行命令，返回第一行第一列的值
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">命令类型（存储过程或SQL语句）</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组</param>
        /// <returns>返回Object对象</returns>
        public static object ExecuteScalar(MySqlConnection conn, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            PrepareCommand(conn, null, cmd, cmdType, cmdText, cmdParms);
            object val = cmd.ExecuteScalar();
            cmd.Parameters.Clear();
            return val;
        }

        /// <summary>
        /// 执行命令或存储过程，返回MySqlDataReader对象
        /// 注意MySqlDataReader对象使用完后必须Close以释放MySqlConnection资源
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">命令类型（存储过程或SQL语句）</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组</param>
        /// <returns></returns>
        public static MySqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            MySqlConnection conn = new MySqlConnection(connectionString);
            try
            {
                PrepareCommand(conn, null, cmd, cmdType, cmdText, cmdParms);
                MySqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                cmd.Parameters.Clear();
                return dr;
            }
            catch
            {
                conn.Close();
                throw;
            }
        }

        /// <summary>
        /// 执行命令或存储过程，返回DataSet对象
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="cmdType">命令类型(存储过程或SQL语句)</param>
        /// <param name="cmdText">SQL语句或存储过程名</param>
        /// <param name="cmdParms">MySqlCommand参数数组(可为null值)</param>
        /// <returns></returns>
        public static DataSet ExecuteDataSet(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] cmdParms)
        {
            MySqlCommand cmd = new MySqlCommand();
            using (MySqlConnection conn = new MySqlConnection(connectionString))
            {
                PrepareCommand(conn, null, cmd, cmdType, cmdText, cmdParms);
                MySqlDataAdapter da = new MySqlDataAdapter(cmd);
                DataSet ds = new DataSet();
                da.Fill(ds);
                conn.Close();
                cmd.Parameters.Clear();
                return ds;
            }
        }
    }

[v从自行车的]

这是一个C#操作MySQL的类 希望有前辈能够帮我说说怎么使用? 最看不懂的就是那方法传递的参数

[郑州高新区WPF小王子]

最看不懂的就是那方法传递的参数 -》别逗了。 人家的注释写的相当的清楚的。 /// 执行命令或存储过程，返回DataSet对象 /// </summary> /// <param name="connectionString">数据库连接字符串</param> /// <param name="cmdType">命令类型(存储过程或SQL语句)</param> /// <param name="cmdText">SQL语句或存储过程名</param> /// <param name="cmdParms">MySqlCommand参数数组(可为null值)</param> 没一个参数都说明了什么意思。。。。

[v从自行车的]

引用 2 楼 duanzi_peng 的回复:

最看不懂的就是那方法传递的参数 -》别逗了。 人家的注释写的相当的清楚的。 /// 执行命令或存储过程，返回DataSet对象 /// </summary> /// <param name="connectionString">数据库连接字符串</param> /// <param name="cmdType">命令类型(存储过程或SQL语句)</param> /// <param name="cmdText">SQL语句或存储过程名</param> /// <param name="cmdParms">MySqlCommand参数数组(可为null值)</param> 没一个参数都说明了什么意思。。。。

他是说得很详尽,但是我还没学到这个 所以看不懂