Code:
/ FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / ProviderBase / WrappedIUnknown.cs / 1 / WrappedIUnknown.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //[....] //[....] //----------------------------------------------------------------------------- namespace System.Data.ProviderBase { using System; using System.Data.Common; using System.Runtime.CompilerServices; using System.Runtime.ConstrainedExecution; using System.Runtime.InteropServices; using System.Security; using System.Security.Permissions; using System.Threading; // We wrap the interface as a native IUnknown IntPtr so that every // thread that creates a connection will fake the correct context when // in transactions, otherwise everything is marshalled. We do this // for two reasons: first for the connection pooler, this is a significant // performance gain, second for the OLE DB provider, it doesn't marshal. internal class WrappedIUnknown : SafeHandle { internal WrappedIUnknown() : base(IntPtr.Zero, true) { } internal WrappedIUnknown(object unknown) : this() { if (null != unknown) { RuntimeHelpers.PrepareConstrainedRegions(); try {} finally { base.handle = Marshal.GetIUnknownForObject(unknown); // } } } public override bool IsInvalid { get { return (IntPtr.Zero == base.handle); } } internal object ComWrapper() { // NOTE: Method, instead of property, to avoid being evaluated at // runtime in the debugger. object value = null; bool mustRelease = false; RuntimeHelpers.PrepareConstrainedRegions(); try { DangerousAddRef(ref mustRelease); IntPtr handle = DangerousGetHandle(); value = System.Runtime.Remoting.Services.EnterpriseServicesHelper.WrapIUnknownWithComObject(handle); } finally { if (mustRelease) { DangerousRelease(); } } return value; } override protected bool ReleaseHandle() { // NOTE: The SafeHandle class guarantees this will be called exactly once. IntPtr ptr = base.handle; base.handle = IntPtr.Zero; if (IntPtr.Zero != ptr) { Marshal.Release(ptr); } return true; } } } // 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
- FormsAuthenticationTicket.cs
- GridToolTip.cs
- WorkflowInspectionServices.cs
- ZipIOBlockManager.cs
- ErrorHandlingReceiver.cs
- OutputCacheModule.cs
- SymLanguageVendor.cs
- SafeNativeMethods.cs
- Utils.cs
- ExtensionFile.cs
- LabelLiteral.cs
- Int64.cs
- SliderAutomationPeer.cs
- FixedPosition.cs
- ValidationRuleCollection.cs
- CompilerParameters.cs
- CodeComment.cs
- FileRecordSequenceHelper.cs
- Rule.cs
- FolderBrowserDialogDesigner.cs
- WorkflowMarkupSerializer.cs
- ObjectPropertyMapping.cs
- HtmlButton.cs
- XmlDataFileEditor.cs
- PageWrapper.cs
- EdmRelationshipRoleAttribute.cs
- RowUpdatedEventArgs.cs
- ExportOptions.cs
- QueryTask.cs
- OrderedDictionaryStateHelper.cs
- BitConverter.cs
- XmlValueConverter.cs
- Array.cs
- MemberAccessException.cs
- WindowsListViewGroupHelper.cs
- SurrogateChar.cs
- Imaging.cs
- SQLConvert.cs
- ParameterElement.cs
- ResourcesChangeInfo.cs
- Rfc2898DeriveBytes.cs
- PaperSource.cs
- ElementMarkupObject.cs
- ContextItemManager.cs
- ColumnClickEvent.cs
- HtmlControl.cs
- CompositeActivityTypeDescriptorProvider.cs
- ToolStripDropDownItem.cs
- XmlReturnWriter.cs
- ExitEventArgs.cs
- AnalyzedTree.cs
- ComponentConverter.cs
- UserPrincipalNameElement.cs
- InternalConfigEventArgs.cs
- Pool.cs
- DocumentGridPage.cs
- BuildResultCache.cs
- GatewayIPAddressInformationCollection.cs
- DbParameterHelper.cs
- BaseDataList.cs
- DelayedRegex.cs
- HtmlWindow.cs
- QueryMath.cs
- CatalogPart.cs
- InputScopeConverter.cs
- MsmqOutputChannel.cs
- LinkButton.cs
- BitmapEffect.cs
- AttributeCollection.cs
- NGCSerializationManager.cs
- Internal.cs
- SoapBinding.cs
- FileSystemEventArgs.cs
- ProcessHost.cs
- Normalization.cs
- QilPatternVisitor.cs
- DefaultMergeHelper.cs
- CookieHandler.cs
- ErrorStyle.cs
- SqlFormatter.cs
- MsmqHostedTransportManager.cs
- RepeatBehaviorConverter.cs
- SessionIDManager.cs
- ChangeProcessor.cs
- TextSelectionProcessor.cs
- XPathSelectionIterator.cs
- DesignerActionItemCollection.cs
- StylusCollection.cs
- CharEnumerator.cs
- InstalledVoice.cs
- TreeNode.cs
- WebEventCodes.cs
- WebPartCollection.cs
- MessageQueueEnumerator.cs
- CheckBoxField.cs
- RegionData.cs
- WsatServiceAddress.cs
- XmlChildNodes.cs
- ChineseLunisolarCalendar.cs
- CreateUserWizardDesigner.cs