Code:
/ FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / clr / src / BCL / System / OleAutBinder.cs / 1 / OleAutBinder.cs
// ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== // This class represents the Ole Automation binder. // #define DISPLAY_DEBUG_INFO namespace System { using System; using System.Runtime.InteropServices; using System.Reflection; using Microsoft.Win32; using CultureInfo = System.Globalization.CultureInfo; // Made serializable in anticipation of this class eventually having state. [Serializable()] internal class OleAutBinder : DefaultBinder { // ChangeType // This binder uses OLEAUT to change the type of the variant. public override Object ChangeType(Object value, Type type, CultureInfo cultureInfo) { Variant myValue = new Variant(value); if (cultureInfo == null) cultureInfo = CultureInfo.CurrentCulture; #if DISPLAY_DEBUG_INFO Console.Write("In OleAutBinder::ChangeType converting variant of type: "); Console.Write(myValue.VariantType); Console.Write(" to type: "); Console.WriteLine(type.Name); #endif if (type.IsByRef) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Striping byref from the type to convert to."); #endif type = type.GetElementType(); } // If we are trying to convert from an object to another type then we don't // need the OLEAUT change type, we can just use the normal COM+ mechanisms. if (!type.IsPrimitive && type.IsInstanceOfType(value)) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Source variant can be assigned to destination type"); #endif return value; } Type srcType = value.GetType(); // Handle converting primitives to enums. if (type.IsEnum && srcType.IsPrimitive) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Converting primitive to enum"); #endif return Enum.Parse(type, value.ToString()); } // Special case the convertion from DBNull. if (srcType == typeof(DBNull)) { // The requested type is a DBNull so no convertion is required. if (type == typeof(DBNull)) return value; // Visual J++ supported converting from DBNull to null so customers // have requested (via a CDCR) that DBNull be convertible to null. // We don't however allow this when converting to a value class, since null // doesn't make sense for these, or to object since this would change existing // semantics. if ((type.IsClass && type != typeof(Object)) || type.IsInterface) return null; } #if FEATURE_COMINTEROP // Use the OA variant lib to convert primitive types. try { #if DISPLAY_DEBUG_INFO Console.WriteLine("Using OAVariantLib.ChangeType() to do the conversion"); #endif // Specify the LocalBool flag to have BOOL values converted to local language rather // than 0 or -1. Object RetObj = OAVariantLib.ChangeType(myValue, type, OAVariantLib.LocalBool, cultureInfo).ToObject(); #if DISPLAY_DEBUG_INFO Console.WriteLine("Object returned from ChangeType is of type: " + RetObj.GetType().Name); #endif return RetObj; } #if DISPLAY_DEBUG_INFO catch(NotSupportedException e) #else catch(NotSupportedException) #endif { #if DISPLAY_DEBUG_INFO Console.Write("Exception thrown: "); Console.WriteLine(e); #endif throw new COMException(Environment.GetResourceString("Interop.COM_TypeMismatch"), unchecked((int)0x80020005)); } #else // !FEATURE_COMINTEROP return base.ChangeType(value, type, cultureInfo); #endif // !FEATURE_COMINTEROP } #if !FEATURE_COMINTEROP // CanChangeType public override bool CanChangeType(Object value, Type type, CultureInfo cultureInfo) { Variant myValue = new Variant(value); if (cultureInfo == null) cultureInfo = CultureInfo.CurrentCulture; #if DISPLAY_DEBUG_INFO Console.Write("In OleAutBinder::CanChangeType converting variant of type: "); Console.Write(myValue.VariantType); Console.Write(" to type: "); Console.WriteLine(type.Name); #endif // If we are trying to convert to variant then there is nothing to do. if (type == typeof(Variant)) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Variant being changed to type variant is always legal"); #endif return true; } if (type.IsByRef) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Striping byref from the type to convert to."); #endif type = type.GetElementType(); } // If we are trying to convert from an object to another type then we don't // need the OLEAUT change type, we can just use the normal COM+ mechanisms. if (!type.IsPrimitive && type.IsInstanceOfType(value)) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Source variant can be assigned to destination type"); #endif return true; } // Handle converting primitives to enums. if (type.IsEnum && value.GetType().IsPrimitive) { #if DISPLAY_DEBUG_INFO Console.WriteLine("Converting primitive to enum"); #endif return true; } return base.CanChangeType(value, type, cultureInfo); } #endif // FEATURE_COMINTEROP } }
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- ContentWrapperAttribute.cs
- DbConnectionPoolCounters.cs
- SortKey.cs
- UInt16Converter.cs
- TemplateField.cs
- Parser.cs
- XmlDictionary.cs
- PrintController.cs
- DataGridLinkButton.cs
- Nullable.cs
- FixedPosition.cs
- SpinWait.cs
- ObjectReaderCompiler.cs
- OletxCommittableTransaction.cs
- HtmlGenericControl.cs
- LookupNode.cs
- ViewUtilities.cs
- DataGridViewCellCollection.cs
- XpsFixedPageReaderWriter.cs
- WorkflowRequestContext.cs
- EventPrivateKey.cs
- ImportCatalogPart.cs
- HwndAppCommandInputProvider.cs
- ListViewContainer.cs
- ReliableMessagingVersionConverter.cs
- SmiContextFactory.cs
- controlskin.cs
- SignatureDescription.cs
- HtmlPageAdapter.cs
- ValuePattern.cs
- XmlLinkedNode.cs
- PropVariant.cs
- ParameterEditorUserControl.cs
- ManagementObjectCollection.cs
- DataObjectCopyingEventArgs.cs
- MediaPlayer.cs
- RuntimeResourceSet.cs
- XmlKeywords.cs
- InternalConfigRoot.cs
- Application.cs
- HttpServerVarsCollection.cs
- MobileControlsSectionHandler.cs
- StringFunctions.cs
- OdbcHandle.cs
- CanExecuteRoutedEventArgs.cs
- MsmqAppDomainProtocolHandler.cs
- CatalogZoneDesigner.cs
- TriggerCollection.cs
- HttpHostedTransportConfiguration.cs
- EncoderParameter.cs
- DataControlField.cs
- OciEnlistContext.cs
- CacheVirtualItemsEvent.cs
- MachineKeySection.cs
- HttpCacheVary.cs
- AutoResizedEvent.cs
- ConfigXmlComment.cs
- ParameterElementCollection.cs
- FlagsAttribute.cs
- XPathParser.cs
- TokenBasedSetEnumerator.cs
- InputProcessorProfiles.cs
- EventLogEntry.cs
- DrawingVisual.cs
- TextEffectCollection.cs
- CharAnimationBase.cs
- VirtualDirectoryMappingCollection.cs
- ToolStripProgressBar.cs
- clipboard.cs
- AtomMaterializerLog.cs
- NetNamedPipeSecurityElement.cs
- CallInfo.cs
- StringKeyFrameCollection.cs
- TextServicesCompartmentEventSink.cs
- LinkedResource.cs
- DecoratedNameAttribute.cs
- EmitterCache.cs
- SafeLocalMemHandle.cs
- HiddenFieldPageStatePersister.cs
- ForceCopyBuildProvider.cs
- TranslateTransform.cs
- LongValidatorAttribute.cs
- ClientSideProviderDescription.cs
- XmlArrayItemAttribute.cs
- ItemCollection.cs
- LinqDataSourceStatusEventArgs.cs
- HttpModuleCollection.cs
- TableLayout.cs
- UiaCoreTypesApi.cs
- GAC.cs
- ValidationSummaryDesigner.cs
- ZipPackage.cs
- VectorAnimation.cs
- InputEventArgs.cs
- ClockGroup.cs
- datacache.cs
- PeerEndPoint.cs
- AttributeCollection.cs
- PageContentCollection.cs
- DeclarativeCatalogPart.cs