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cmd.ExecuteReader(CommandBehavior.CloseConnection); cmd.Parameters.Clear(); return myReader; } catch (MySql.Data.MySqlClient.MySqlException e) { throw e; } // finally // { // cmd.Dispose(); // connection.Close(); // } } /// <summary> /// 执行查询语句，返回DataSet /// </summary> /// <param name="SQLString">查询语句</param> /// <returns>DataSet</returns> public static DataSet Query(string SQLString, params MySqlParameter[] cmdParms) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { MySqlCommand cmd = new MySqlCommand(); PrepareCommand(cmd, connection, null, SQLString, cmdParms); using (MySqlDataAdapter da = new MySqlDataAdapter(cmd)) { DataSet ds = new DataSet(); try { da.Fill(ds, "ds"); cmd.Parameters.Clear(); } catch (MySql.Data.MySqlClient.MySqlException ex) { throw new Exception(ex.Message); } return ds; } } } private static void PrepareCommand(MySqlCommand cmd, MySqlConnection conn, MySqlTransaction trans, 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 = CommandType.Text;//cmdType; if (cmdParms != null) { foreach (MySqlParameter parameter in cmdParms) { if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) && (parameter.Value == null)) { parameter.Value = DBNull.Value; } cmd.Parameters.Add(parameter); } } } #endregion #region 执行带参数的存储过程 /// <summary> /// 执行带参数的存储过程 /// </summary> /// <param name="SQLString"></param> /// <param name="cmdParms"></param> /// <returns></returns> public static object ExecuteProc(string SQLString, params MySqlParameter[] cmdParms) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); cmd.CommandType = CommandType.StoredProcedure; int rows = cmd.ExecuteNonQuery(); Console.WriteLine("返回值为 " + cmdParms[1].Value); cmd.Parameters.Clear(); return rows; } catch (MySql.Data.MySqlClient.MySqlException e) { connection.Close(); throw e; } } } } /// <summary> /// 存储过程查询DataTable /// </summary> /// <param name="SQLString"></param> /// <param name="cmdParms"></param> /// <returns></returns> public static DataTable QueryProc(string SQLString, params MySqlParameter[] cmdParms) { using (MySqlConnection connection = new MySqlConnection(connectionString)) { using (MySqlCommand cmd = new MySqlCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); cmd.CommandType = CommandType.StoredProcedure; MySqlDataAdapter adapter = new MySqlDataAdapter(cmd); DataTable dt = new DataTable(); adapter.Fill(dt); cmd.Parameters.Clear(); return dt; } catch (MySql.Data.MySqlClient.MySqlException e) { connection.Close(); throw e; } } } } #endregion } }