Code:
/ DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / ProviderBase / DataReaderContainer.cs / 1 / DataReaderContainer.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //----------------------------------------------------------------------------- namespace System.Data.ProviderBase { using System; using System.Data; using System.Data.Common; using System.Diagnostics; internal abstract class DataReaderContainer { protected readonly IDataReader _dataReader; protected int _fieldCount; static internal DataReaderContainer Create(IDataReader dataReader, bool returnProviderSpecificTypes) { if (returnProviderSpecificTypes) { DbDataReader providerSpecificDataReader = (dataReader as DbDataReader); if (null != providerSpecificDataReader) { return new ProviderSpecificDataReader(dataReader, providerSpecificDataReader); } } return new CommonLanguageSubsetDataReader(dataReader); } protected DataReaderContainer(IDataReader dataReader) { Debug.Assert(null != dataReader, "null dataReader"); _dataReader = dataReader; } internal int FieldCount { get { return _fieldCount; } } internal abstract bool ReturnProviderSpecificTypes { get; } protected abstract int VisibleFieldCount { get; } internal abstract Type GetFieldType(int ordinal); internal abstract object GetValue(int ordinal); internal abstract int GetValues(object[] values); internal string GetName(int ordinal) { string fieldName = _dataReader.GetName(ordinal); Debug.Assert(null != fieldName, "null GetName"); return ((null != fieldName) ? fieldName : ""); } internal DataTable GetSchemaTable() { return _dataReader.GetSchemaTable(); } internal bool NextResult() { _fieldCount = 0; if (_dataReader.NextResult()) { _fieldCount = VisibleFieldCount; return true; } return false; } internal bool Read() { return _dataReader.Read(); } private sealed class ProviderSpecificDataReader : DataReaderContainer { private DbDataReader _providerSpecificDataReader; internal ProviderSpecificDataReader(IDataReader dataReader, DbDataReader dbDataReader) : base(dataReader) { Debug.Assert(null != dataReader, "null dbDataReader"); _providerSpecificDataReader = dbDataReader; _fieldCount = VisibleFieldCount; } internal override bool ReturnProviderSpecificTypes { get { return true; } } protected override int VisibleFieldCount { get { int fieldCount = _providerSpecificDataReader.VisibleFieldCount; Debug.Assert(0 <= fieldCount, "negative FieldCount"); return ((0 <= fieldCount) ? fieldCount : 0); } } internal override Type GetFieldType(int ordinal) { Type fieldType = _providerSpecificDataReader.GetProviderSpecificFieldType(ordinal); Debug.Assert(null != fieldType, "null FieldType"); return fieldType; } internal override object GetValue(int ordinal) { return _providerSpecificDataReader.GetProviderSpecificValue(ordinal); } internal override int GetValues(object[] values) { return _providerSpecificDataReader.GetProviderSpecificValues(values); } } private sealed class CommonLanguageSubsetDataReader : DataReaderContainer { internal CommonLanguageSubsetDataReader(IDataReader dataReader ) : base(dataReader) { _fieldCount = VisibleFieldCount; } internal override bool ReturnProviderSpecificTypes { get { return false; } } protected override int VisibleFieldCount { get { int fieldCount = _dataReader.FieldCount; Debug.Assert(0 <= fieldCount, "negative FieldCount"); return ((0 <= fieldCount) ? fieldCount : 0); } } internal override Type GetFieldType(int ordinal) { return _dataReader.GetFieldType(ordinal); } internal override object GetValue(int ordinal) { return _dataReader.GetValue(ordinal); } internal override int GetValues(object[] values) { return _dataReader.GetValues(values); } } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu

This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- dbdatarecord.cs
- GridViewCommandEventArgs.cs
- WeakHashtable.cs
- UpdatePanelTrigger.cs
- HMACMD5.cs
- _HelperAsyncResults.cs
- SizeFConverter.cs
- ControlOperationInvoker.cs
- ToolTipAutomationPeer.cs
- NavigationFailedEventArgs.cs
- EncodingDataItem.cs
- XmlSchemaRedefine.cs
- BatchParser.cs
- BufferedWebEventProvider.cs
- ExecutionEngineException.cs
- RemoteWebConfigurationHostServer.cs
- TextBox.cs
- MimeMultiPart.cs
- CodePageEncoding.cs
- CodeActivity.cs
- ArrangedElement.cs
- XmlUtil.cs
- EditorPart.cs
- AnnotationHelper.cs
- GradientStop.cs
- DataMemberFieldEditor.cs
- ButtonDesigner.cs
- designeractionlistschangedeventargs.cs
- ConstructorExpr.cs
- DataGridViewImageCell.cs
- SynchronizationLockException.cs
- CompilationLock.cs
- Char.cs
- EventLogPermissionAttribute.cs
- AddressUtility.cs
- ToolStripDesignerAvailabilityAttribute.cs
- Stream.cs
- MulticastNotSupportedException.cs
- unitconverter.cs
- ToolStripDropDownClosingEventArgs.cs
- _ListenerAsyncResult.cs
- ScriptIgnoreAttribute.cs
- WS2007FederationHttpBinding.cs
- ObjectDataSource.cs
- DateTimeFormatInfoScanner.cs
- TransformerInfoCollection.cs
- DecoratedNameAttribute.cs
- DbConnectionPoolIdentity.cs
- SendingRequestEventArgs.cs
- EventHandlerList.cs
- BoolLiteral.cs
- DataListCommandEventArgs.cs
- Calendar.cs
- PriorityQueue.cs
- MailWebEventProvider.cs
- TextEffectResolver.cs
- BackgroundFormatInfo.cs
- XmlJsonReader.cs
- QueryReaderSettings.cs
- ADConnectionHelper.cs
- EnumMemberAttribute.cs
- PixelShader.cs
- GreenMethods.cs
- HighlightComponent.cs
- CopyOfAction.cs
- EditorBrowsableAttribute.cs
- Msmq4SubqueuePoisonHandler.cs
- OperationDescriptionCollection.cs
- ADConnectionHelper.cs
- OdbcParameter.cs
- UInt32.cs
- ScriptServiceAttribute.cs
- RichTextBox.cs
- Command.cs
- GeneralTransform3DGroup.cs
- BaseValidator.cs
- CodeDirectionExpression.cs
- WindowsAltTab.cs
- TemplateAction.cs
- uribuilder.cs
- GeneralTransform3DGroup.cs
- TextEditorSelection.cs
- DiagnosticsConfiguration.cs
- DataServiceClientException.cs
- DataGridViewCellMouseEventArgs.cs
- SeverityFilter.cs
- ProfileManager.cs
- SelectingProviderEventArgs.cs
- ConcurrentDictionary.cs
- XmlBinaryWriterSession.cs
- SingleSelectRootGridEntry.cs
- LinqToSqlWrapper.cs
- TaiwanCalendar.cs
- FileDialog_Vista_Interop.cs
- X500Name.cs
- SerTrace.cs
- Math.cs
- ObjectManager.cs
- ConnectionAcceptor.cs
- CompensationHandlingFilter.cs