Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / Services / Messaging / System / Messaging / MessageQueueEnumerator.cs / 1305376 / MessageQueueEnumerator.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //----------------------------------------------------------------------------- using INTPTR_INTPTRCAST = System.IntPtr; namespace System.Messaging { using System.Runtime.InteropServices; using System.Diagnostics; using System.Diagnostics.CodeAnalysis; using System; using System.Collections; using System.Messaging.Interop; using System.Globalization; ////// /// public class MessageQueueEnumerator : MarshalByRefObject, IEnumerator, IDisposable { private MessageQueueCriteria criteria; private LocatorHandle locatorHandle= System.Messaging.Interop.LocatorHandle.InvalidHandle; private MessageQueue currentMessageQueue; private bool checkSecurity; private bool disposed; ///Provides (forward-only) cursor semantics to enumerate the queues on a /// computer. ////// I'm assuming all the queues have to /// be /// on the same computer. Is this the case? Do we want to translate this reference /// to "cursor semantics" into English, or is it okay as it stands? Will the users /// understand the concept of a cursor? /// ////// internal MessageQueueEnumerator(MessageQueueCriteria criteria) { this.criteria = criteria; this.checkSecurity = true; } /// /// internal MessageQueueEnumerator(MessageQueueCriteria criteria, bool checkSecurity) { this.criteria = criteria; this.checkSecurity = checkSecurity; } /// /// /// Returns the current MessageQueue of the enumeration. /// Before the first call to MoveNext and following a call to MoveNext that /// returned false an InvalidOperationException will be thrown. Multiple /// calls to Current with no intervening calls to MoveNext will return the /// same MessageQueue object. /// public MessageQueue Current { get { if (this.currentMessageQueue == null) throw new InvalidOperationException(Res.GetString(Res.NoCurrentMessageQueue)); return this.currentMessageQueue; } } ////// object IEnumerator.Current { get { return this.Current; } } /// /// /// public void Close() { if (!this.locatorHandle.IsInvalid) { this.locatorHandle.Close(); this.currentMessageQueue = null; } } ///Frees the resources associated with the enumerator. ////// /// [SuppressMessage("Microsoft.Usage", "CA2213:DisposableFieldsShouldBeDisposed")] public void Dispose() { Dispose(true); GC.SuppressFinalize(this); } ////// /// [SuppressMessage("Microsoft.Usage", "CA2213:DisposableFieldsShouldBeDisposed", MessageId="currentMessageQueue")] protected virtual void Dispose(bool disposing) { this.Close(); this.disposed = true; } ////// ////// /// ~MessageQueueEnumerator() { Dispose(false); } ////// /// public IntPtr LocatorHandle { get { return this.Handle.DangerousGetHandle(); } } LocatorHandle Handle { get { if (this.locatorHandle.IsInvalid) { //Cannot allocate the locatorHandle if the object has been disposed, since finalization has been suppressed. if (this.disposed) throw new ObjectDisposedException(GetType().Name); if (this.checkSecurity) { MessageQueuePermission permission = new MessageQueuePermission(MessageQueuePermissionAccess.Browse, MessageQueuePermission.Any); permission.Demand(); } Columns columns = new Columns(2); LocatorHandle enumHandle; columns.AddColumnId(NativeMethods.QUEUE_PROPID_PATHNAME); //Adding the instance property avoids accessing the DS a second //time, the formatName can be resolved by calling MQInstanceToFormatName columns.AddColumnId(NativeMethods.QUEUE_PROPID_INSTANCE); int status; if (this.criteria != null) status = UnsafeNativeMethods.MQLocateBegin(null, this.criteria.Reference, columns.GetColumnsRef(), out enumHandle); else status = UnsafeNativeMethods.MQLocateBegin(null, null, columns.GetColumnsRef(), out enumHandle); if (MessageQueue.IsFatalError(status)) throw new MessageQueueException(status); this.locatorHandle = enumHandle; } return this.locatorHandle; } } ///Indicates the native Message Queuing handle used to locate queues in a network. This /// property is read-only. ////// /// public bool MoveNext() { MQPROPVARIANTS[] array = new MQPROPVARIANTS[2]; int propertyCount; string currentItem; byte[] currentGuid = new byte[16]; string machineName = null; if (this.criteria != null && this.criteria.FilterMachine) { if (this.criteria.MachineName.CompareTo(".") == 0) machineName = MessageQueue.ComputerName + "\\"; else machineName = this.criteria.MachineName + "\\"; } do { propertyCount = 2; int status; status = SafeNativeMethods.MQLocateNext(this.Handle, ref propertyCount, array); if (MessageQueue.IsFatalError(status)) throw new MessageQueueException(status); if (propertyCount != 2) { this.currentMessageQueue = null; return false; } //Using Unicode API even on Win9x currentItem = Marshal.PtrToStringUni(array[0].ptr); Marshal.Copy(array[1].ptr, currentGuid, 0, 16); //MSMQ allocated this memory, lets free it. SafeNativeMethods.MQFreeMemory(array[0].ptr); SafeNativeMethods.MQFreeMemory(array[1].ptr); } while (machineName != null && (machineName.Length >= currentItem.Length || String.Compare(machineName, 0, currentItem, 0, machineName.Length, true, CultureInfo.InvariantCulture) != 0)); this.currentMessageQueue = new MessageQueue(currentItem, new Guid(currentGuid)); return true; } ////// Advances the enumerator to the next queue of the enumeration, if one /// is currently available. ////// /// public void Reset() { this.Close(); } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007.Resets the cursor, so it points to the head of the list.. ///
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- SafeNativeMethods.cs
- TransformerInfo.cs
- ContractSearchPattern.cs
- ToolBarButtonDesigner.cs
- XamlStyleSerializer.cs
- ComponentChangingEvent.cs
- XmlSortKeyAccumulator.cs
- OperationResponse.cs
- HeaderCollection.cs
- IntegrationExceptionEventArgs.cs
- DbModificationCommandTree.cs
- GridItemCollection.cs
- RegexRunner.cs
- AsyncResult.cs
- TransformPattern.cs
- ControlAdapter.cs
- ChannelRequirements.cs
- _LoggingObject.cs
- ScriptManagerProxy.cs
- ConfigXmlSignificantWhitespace.cs
- MenuTracker.cs
- Section.cs
- XmlSchemaSubstitutionGroup.cs
- ThicknessAnimationUsingKeyFrames.cs
- clipboard.cs
- InsufficientMemoryException.cs
- PeerApplication.cs
- RequestBringIntoViewEventArgs.cs
- ProtectedProviderSettings.cs
- DoWorkEventArgs.cs
- ComponentRenameEvent.cs
- CounterSampleCalculator.cs
- VarInfo.cs
- AudioBase.cs
- CodeNamespace.cs
- Sequence.cs
- XmlSchemaParticle.cs
- CacheRequest.cs
- DataGrid.cs
- InternalDispatchObject.cs
- OpCopier.cs
- FormViewRow.cs
- StreamInfo.cs
- WebBrowserPermission.cs
- LazyTextWriterCreator.cs
- Opcode.cs
- _SpnDictionary.cs
- ElementAtQueryOperator.cs
- SqlRowUpdatedEvent.cs
- TableRowsCollectionEditor.cs
- ScriptResourceDefinition.cs
- XPathDescendantIterator.cs
- IconBitmapDecoder.cs
- SoapFormatExtensions.cs
- RoleManagerEventArgs.cs
- MemberRelationshipService.cs
- AlphabetConverter.cs
- ValidationResult.cs
- SafeProcessHandle.cs
- ObjectDataSourceView.cs
- CrossAppDomainChannel.cs
- DateTimeConstantAttribute.cs
- EncodingTable.cs
- SqlMethodTransformer.cs
- MediaScriptCommandRoutedEventArgs.cs
- AsyncCodeActivityContext.cs
- DocumentEventArgs.cs
- CookieHandler.cs
- DataSourceCache.cs
- Control.cs
- Message.cs
- XmlAttributeProperties.cs
- TemplateApplicationHelper.cs
- Comparer.cs
- SqlClientFactory.cs
- CompileXomlTask.cs
- TextAutomationPeer.cs
- LabelDesigner.cs
- MetadataArtifactLoaderFile.cs
- CurrentChangedEventManager.cs
- ClientSponsor.cs
- CancelEventArgs.cs
- ExpressionNode.cs
- DoubleCollection.cs
- PersonalizableTypeEntry.cs
- ObjectNavigationPropertyMapping.cs
- Formatter.cs
- DataGridViewSelectedCellCollection.cs
- DataServiceResponse.cs
- WebPartsPersonalization.cs
- OdbcInfoMessageEvent.cs
- ObjectCloneHelper.cs
- CompilerGlobalScopeAttribute.cs
- QilTargetType.cs
- HostedElements.cs
- UnsafeMethods.cs
- ScriptRegistrationManager.cs
- XmlNodeList.cs
- ResponseStream.cs
- TypeTypeConverter.cs