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C# OleDbDataReader.InitializeIMultipleResults方法代码示例

本文整理汇总了C#中System.Data.OleDb.OleDbDataReader.InitializeIMultipleResults方法的典型用法代码示例。如果您正苦于以下问题:C# OleDbDataReader.InitializeIMultipleResults方法的具体用法?C# OleDbDataReader.InitializeIMultipleResults怎么用?C# OleDbDataReader.InitializeIMultipleResults使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在System.Data.OleDb.OleDbDataReader的用法示例。


在下文中一共展示了OleDbDataReader.InitializeIMultipleResults方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。

示例1: ExecuteReaderInternal

        private OleDbDataReader ExecuteReaderInternal(CommandBehavior behavior, string method) {
            OleDbDataReader dataReader = null;
            OleDbException nextResultsFailure = null;
            int state = ODB.InternalStateClosed;
            try {
                ValidateConnectionAndTransaction(method);

                if (0 != (CommandBehavior.SingleRow & behavior)) {
                    // CommandBehavior.SingleRow implies CommandBehavior.SingleResult
                    behavior |= CommandBehavior.SingleResult;
                }

                object executeResult;
                int resultType;

                switch(CommandType) {
                case 0: // uninitialized CommandType.Text
                case CommandType.Text:
                case CommandType.StoredProcedure:
                    resultType = ExecuteCommand(behavior, out executeResult);
                    break;

                case CommandType.TableDirect:
                    resultType = ExecuteTableDirect(behavior, out executeResult);
                    break;

                default:
                    throw ADP.InvalidCommandType(CommandType);
                }

                if (_executeQuery) {
                    try {
                        dataReader = new OleDbDataReader(_connection, this, 0, this.commandBehavior);

                        switch(resultType) {
                        case ODB.ExecutedIMultipleResults:
                            dataReader.InitializeIMultipleResults(executeResult);
                            dataReader.NextResult();
                            break;
                        case ODB.ExecutedIRowset:
                            dataReader.InitializeIRowset(executeResult, ChapterHandle.DB_NULL_HCHAPTER, _recordsAffected);
                            dataReader.BuildMetaInfo();
                            dataReader.HasRowsRead();
                            break;
                        case ODB.ExecutedIRow:
                            dataReader.InitializeIRow(executeResult, _recordsAffected);
                            dataReader.BuildMetaInfo();
                            break;
                        case ODB.PrepareICommandText:
                            if (!_isPrepared) {
                                PrepareCommandText(2);
                            }
                            OleDbDataReader.GenerateSchemaTable(dataReader, _icommandText, behavior);
                            break;
                        default:
                            Debug.Assert(false, "ExecuteReaderInternal: unknown result type");
                            break;
                        }
                        executeResult = null;
                        _hasDataReader = true;
                        _connection.AddWeakReference(dataReader, OleDbReferenceCollection.DataReaderTag);

                        // command stays in the executing state until the connection
                        // has a datareader to track for it being closed
                        state = ODB.InternalStateOpen; // MDAC 72655
                    }
                    finally {
                        if (ODB.InternalStateOpen != state) {
                            this.canceling = true;
                            if (null != dataReader) {
                                ((IDisposable) dataReader).Dispose();
                                dataReader = null;
                            }
                        }
                    }
                    Debug.Assert(null != dataReader, "ExecuteReader should never return a null DataReader");
                }
                else { // optimized code path for ExecuteNonQuery to not create a OleDbDataReader object
                    try {
                        if (ODB.ExecutedIMultipleResults == resultType) {
                            UnsafeNativeMethods.IMultipleResults multipleResults = (UnsafeNativeMethods.IMultipleResults) executeResult;

                            // may cause a Connection.ResetState which closes connection
                            nextResultsFailure = OleDbDataReader.NextResults(multipleResults, _connection, this, out _recordsAffected);
                        }
                    }
                    finally {
                        try {
                            if (null != executeResult) {
                                Marshal.ReleaseComObject(executeResult);
                                executeResult = null;
                            }
                            CloseFromDataReader(ParameterBindings);
                        }
                        catch(Exception e) {
                            // 
                            if (!ADP.IsCatchableExceptionType(e)) {
                                throw;
                            }
                            if (null != nextResultsFailure) {
//.........这里部分代码省略.........
开发者ID:krytht,项目名称:DotNetReferenceSource,代码行数:101,代码来源:OleDbCommand.cs

示例2: ExecuteReaderInternal

        private OleDbDataReader ExecuteReaderInternal(CommandBehavior behavior, string method)
        {
            OleDbDataReader dataReader = null;
            OleDbException previous = null;
            int num2 = 0;
            try
            {
                object obj2;
                int num;
                this.ValidateConnectionAndTransaction(method);
                if ((CommandBehavior.SingleRow & behavior) != CommandBehavior.Default)
                {
                    behavior |= CommandBehavior.SingleResult;
                }
                switch (this.CommandType)
                {
                    case ((System.Data.CommandType) 0):
                    case System.Data.CommandType.Text:
                    case System.Data.CommandType.StoredProcedure:
                        num = this.ExecuteCommand(behavior, out obj2);
                        break;

                    case System.Data.CommandType.TableDirect:
                        num = this.ExecuteTableDirect(behavior, out obj2);
                        break;

                    default:
                        throw ADP.InvalidCommandType(this.CommandType);
                }
                if (this._executeQuery)
                {
                    try
                    {
                        dataReader = new OleDbDataReader(this._connection, this, 0, this.commandBehavior);
                        switch (num)
                        {
                            case 0:
                                dataReader.InitializeIMultipleResults(obj2);
                                dataReader.NextResult();
                                break;

                            case 1:
                                dataReader.InitializeIRowset(obj2, ChapterHandle.DB_NULL_HCHAPTER, this._recordsAffected);
                                dataReader.BuildMetaInfo();
                                dataReader.HasRowsRead();
                                break;

                            case 2:
                                dataReader.InitializeIRow(obj2, this._recordsAffected);
                                dataReader.BuildMetaInfo();
                                break;

                            case 3:
                                if (!this._isPrepared)
                                {
                                    this.PrepareCommandText(2);
                                }
                                OleDbDataReader.GenerateSchemaTable(dataReader, this._icommandText, behavior);
                                break;
                        }
                        obj2 = null;
                        this._hasDataReader = true;
                        this._connection.AddWeakReference(dataReader, 2);
                        num2 = 1;
                        return dataReader;
                    }
                    finally
                    {
                        if (1 != num2)
                        {
                            this.canceling = true;
                            if (dataReader != null)
                            {
                                dataReader.Dispose();
                                dataReader = null;
                            }
                        }
                    }
                }
                try
                {
                    if (num == 0)
                    {
                        UnsafeNativeMethods.IMultipleResults imultipleResults = (UnsafeNativeMethods.IMultipleResults) obj2;
                        previous = OleDbDataReader.NextResults(imultipleResults, this._connection, this, out this._recordsAffected);
                    }
                }
                finally
                {
                    try
                    {
                        if (obj2 != null)
                        {
                            Marshal.ReleaseComObject(obj2);
                            obj2 = null;
                        }
                        this.CloseFromDataReader(this.ParameterBindings);
                    }
                    catch (Exception exception3)
                    {
//.........这里部分代码省略.........
开发者ID:pritesh-mandowara-sp,项目名称:DecompliedDotNetLibraries,代码行数:101,代码来源:OleDbCommand.cs


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