コード例 #1
0
        /// <summary>
        /// Advances the MySqlDataReader to the next record.
        /// </summary>
        /// <returns></returns>
        public override bool Read()
        {
            if (!isOpen)
            {
                throw new MySqlException("Invalid attempt to Read when reader is closed.");
            }
            if (resultSet == null)
            {
                return(false);
            }

            try
            {
                return(resultSet.NextRow(commandBehavior));
            }
            catch (TimeoutException tex)
            {
                connection.HandleTimeoutOrThreadAbort(tex);
                throw;                 // unreached
            }
            catch (MySqlException ex)
            {
                if (ex.IsFatal)
                {
                    connection.Abort();
                }

                if (ex.IsQueryAborted)
                {
                    throw;
                }

                throw new MySqlException(ResourceStrings.FatalErrorDuringRead, ex);
            }
        }
コード例 #2
0
        /// <include file='docs/mysqlcommand.xml' path='docs/ExecuteReader1/*'/>
        public new MySqlDataReader ExecuteReader(CommandBehavior behavior)
        {
            bool success = false;

            CheckState();
            Driver driver = connection.driver;

            lock (driver)
            {
                // We have to recheck that there is no reader, after we got the lock
                if (connection.Reader != null)
                {
                    throw new MySqlException(Resources.DataReaderOpen);
                }
                System.Transactions.Transaction curTrans = System.Transactions.Transaction.Current;
                if (curTrans != null)
                {
                    bool inRollback = false;
                    if (driver.CurrentTransaction != null)
                    {
                        inRollback = driver.CurrentTransaction.InRollback;
                    }
                    if (!inRollback)
                    {
                        TransactionStatus status = TransactionStatus.InDoubt;
                        try
                        {
                            // in some cases (during state transitions) this throws
                            // an exception. Ignore exceptions, we're only interested
                            // whether transaction was aborted or not.
                            status = curTrans.TransactionInformation.Status;
                        }
                        catch (TransactionException)
                        {
                        }
                        if (status == TransactionStatus.Aborted)
                        {
                            throw new TransactionAbortedException();
                        }
                    }
                }

                commandTimer = new CommandTimer(connection, CommandTimeout);

                lastInsertedId = -1;
                cmdText        = cmdText.Trim();
                if (String.IsNullOrEmpty(cmdText))
                {
                    throw new InvalidOperationException(Resources.CommandTextNotInitialized);
                }

                string sql = cmdText.Trim(';');

                if (CommandType == CommandType.TableDirect)
                {
                    sql = "SELECT * FROM " + sql;
                }

                // if we are on a replicated connection, we are only allow readonly statements
                if (connection.Settings.Replication && !InternallyCreated)
                {
                    EnsureCommandIsReadOnly(sql);
                }

                if (statement == null || !statement.IsPrepared)
                {
                    if (CommandType == CommandType.StoredProcedure)
                    {
                        statement = new StoredProcedure(this, sql);
                    }
                    else
                    {
                        statement = new PreparableStatement(this, sql);
                    }
                }

                // stored procs are the only statement type that need do anything during resolve
                statement.Resolve(false);

                // Now that we have completed our resolve step, we can handle our
                // command behaviors
                HandleCommandBehaviors(behavior);

                updatedRowCount = -1;
                try
                {
                    MySqlDataReader reader = new MySqlDataReader(this, statement, behavior);
                    connection.Reader = reader;
                    canceled          = false;
                    // execute the statement
                    statement.Execute();
                    // wait for data to return
                    reader.NextResult();
                    success = true;
                    return(reader);
                }
                catch (TimeoutException tex)
                {
                    connection.HandleTimeoutOrThreadAbort(tex);
                    throw; //unreached
                }
                catch (ThreadAbortException taex)
                {
                    connection.HandleTimeoutOrThreadAbort(taex);
                    throw;
                }
                catch (IOException ioex)
                {
                    connection.Abort(); // Closes connection without returning it to the pool
                    throw new MySqlException(Resources.FatalErrorDuringExecute, ioex);
                }
                catch (MySqlException ex)
                {
                    if (ex.InnerException is TimeoutException)
                    {
                        throw; // already handled
                    }
                    try
                    {
                        ResetReader();
                        ResetSqlSelectLimit();
                    }
                    catch (Exception)
                    {
                        // Reset SqlLimit did not work, connection is hosed.
                        Connection.Abort();
                        throw new MySqlException(ex.Message, true, ex);
                    }

                    // if we caught an exception because of a cancel, then just return null
                    if (ex.IsQueryAborted)
                    {
                        return(null);
                    }
                    if (ex.IsFatal)
                    {
                        Connection.Close();
                    }
                    if (ex.Number == 0)
                    {
                        throw new MySqlException(Resources.FatalErrorDuringExecute, ex);
                    }
                    throw;
                }
                finally
                {
                    if (connection != null)
                    {
                        if (connection.Reader == null)
                        {
                            // Something went seriously wrong,  and reader would not
                            // be able to clear timeout on closing.
                            // So we clear timeout here.
                            ClearCommandTimer();
                        }
                        if (!success)
                        {
                            // ExecuteReader failed.Close Reader and set to null to
                            // prevent subsequent errors with DataReaderOpen
                            ResetReader();
                        }
                    }
                }
            }
        }