Code:
/ Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / Orcas / NetFXw7 / wpf / src / Core / CSharp / MS / Internal / Automation / EventPropertyMap.cs / 1 / EventPropertyMap.cs
//---------------------------------------------------------------------------- // //// Copyright (C) Microsoft Corporation. All rights reserved. // // // // Description: // Accessibility event map classes are used to determine if, and how many // listeners there are for events and property changes. // // History: // 07/23/2003 : BrendanM Ported to WCP // //--------------------------------------------------------------------------- using System; using System.Collections; using System.Windows; using System.Diagnostics; namespace MS.Internal.Automation { // Manages the property map that is used to determine if there are // Automation clients interested in properties. internal class EventPropertyMap { //----------------------------------------------------- // // Constructors // //----------------------------------------------------- #region Constructors // static class, private ctor to prevent creation private EventPropertyMap() { } #endregion Constructors //------------------------------------------------------ // // Internal Methods // //----------------------------------------------------- #region Internal Methods // Called during queueing of property change events to check if there are any // listeners that are interested in this property. Returns true if there are // else false. This function could be called frequently; it must be fast. internal static bool IsInterestingDP(DependencyProperty dp) { using (_propertyLock.ReadLock) { if (_propertyTable != null && _propertyTable.ContainsKey(dp)) { return true; } } return false; } // Updates the list of DynamicProperties that are currently being listened to. // Called by AccEvent class when certain events are added. // // Returns: true if the event property map was created during this call and // false if the property map was not created during this call. internal static bool AddPropertyNotify(DependencyProperty [] properties) { if (properties == null) return false; bool createdMap = false; using (_propertyLock.WriteLock) { // If it doesn't exist, create the property map (key=dp value=listener count) if (_propertyTable == null) { // Up to 20 properties before resize and // small load factor optimizes for speed _propertyTable = new Hashtable(20, .1f); createdMap = true; } int cDPStart = _propertyTable.Count; // properties is an array of the properties one listener is interested in foreach (DependencyProperty dp in properties) { if (dp == null) continue; int cDP = 0; // If the property is in the table, increment it's count if (_propertyTable.ContainsKey(dp)) { cDP = (int)_propertyTable[dp]; } cDP++; _propertyTable[dp] = cDP; } } return createdMap; } // Updates the list of DynamicProperties that are currently being listened to. // Called by AccEvent class when removing certain events. // Returns: true if the property table is empty after this operation. internal static bool RemovePropertyNotify(DependencyProperty [] properties) { Debug.Assert(properties != null); bool isEmpty = false; using (_propertyLock.WriteLock) { if (_propertyTable != null) { int cDPStart = _propertyTable.Count; // properties is an array of the properties one listener is no longer interested in foreach (DependencyProperty dp in properties) { if (_propertyTable.ContainsKey(dp)) { int cDP = (int)_propertyTable[dp]; // Update or remove the entry based on remaining listeners cDP--; if (cDP > 0) { _propertyTable[dp] = cDP; } else { _propertyTable.Remove(dp); } } } // If there are no more properties in the map then delete it; the idea is if there // are no listeners, don't make the property system do extra work. if (_propertyTable.Count == 0) { _propertyTable = null; } } isEmpty = (_propertyTable == null); } return isEmpty; } #endregion Internal Methods //------------------------------------------------------ // // Private Fields // //------------------------------------------------------ #region Private Fields // static class, no instance data... private static ReaderWriterLockWrapper _propertyLock = new ReaderWriterLockWrapper(); private static Hashtable _propertyTable; // key=DP, data=listener count #endregion Private Fields } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved. //---------------------------------------------------------------------------- // //// Copyright (C) Microsoft Corporation. All rights reserved. // // // // Description: // Accessibility event map classes are used to determine if, and how many // listeners there are for events and property changes. // // History: // 07/23/2003 : BrendanM Ported to WCP // //--------------------------------------------------------------------------- using System; using System.Collections; using System.Windows; using System.Diagnostics; namespace MS.Internal.Automation { // Manages the property map that is used to determine if there are // Automation clients interested in properties. internal class EventPropertyMap { //----------------------------------------------------- // // Constructors // //----------------------------------------------------- #region Constructors // static class, private ctor to prevent creation private EventPropertyMap() { } #endregion Constructors //------------------------------------------------------ // // Internal Methods // //----------------------------------------------------- #region Internal Methods // Called during queueing of property change events to check if there are any // listeners that are interested in this property. Returns true if there are // else false. This function could be called frequently; it must be fast. internal static bool IsInterestingDP(DependencyProperty dp) { using (_propertyLock.ReadLock) { if (_propertyTable != null && _propertyTable.ContainsKey(dp)) { return true; } } return false; } // Updates the list of DynamicProperties that are currently being listened to. // Called by AccEvent class when certain events are added. // // Returns: true if the event property map was created during this call and // false if the property map was not created during this call. internal static bool AddPropertyNotify(DependencyProperty [] properties) { if (properties == null) return false; bool createdMap = false; using (_propertyLock.WriteLock) { // If it doesn't exist, create the property map (key=dp value=listener count) if (_propertyTable == null) { // Up to 20 properties before resize and // small load factor optimizes for speed _propertyTable = new Hashtable(20, .1f); createdMap = true; } int cDPStart = _propertyTable.Count; // properties is an array of the properties one listener is interested in foreach (DependencyProperty dp in properties) { if (dp == null) continue; int cDP = 0; // If the property is in the table, increment it's count if (_propertyTable.ContainsKey(dp)) { cDP = (int)_propertyTable[dp]; } cDP++; _propertyTable[dp] = cDP; } } return createdMap; } // Updates the list of DynamicProperties that are currently being listened to. // Called by AccEvent class when removing certain events. // Returns: true if the property table is empty after this operation. internal static bool RemovePropertyNotify(DependencyProperty [] properties) { Debug.Assert(properties != null); bool isEmpty = false; using (_propertyLock.WriteLock) { if (_propertyTable != null) { int cDPStart = _propertyTable.Count; // properties is an array of the properties one listener is no longer interested in foreach (DependencyProperty dp in properties) { if (_propertyTable.ContainsKey(dp)) { int cDP = (int)_propertyTable[dp]; // Update or remove the entry based on remaining listeners cDP--; if (cDP > 0) { _propertyTable[dp] = cDP; } else { _propertyTable.Remove(dp); } } } // If there are no more properties in the map then delete it; the idea is if there // are no listeners, don't make the property system do extra work. if (_propertyTable.Count == 0) { _propertyTable = null; } } isEmpty = (_propertyTable == null); } return isEmpty; } #endregion Internal Methods //------------------------------------------------------ // // Private Fields // //------------------------------------------------------ #region Private Fields // static class, no instance data... private static ReaderWriterLockWrapper _propertyLock = new ReaderWriterLockWrapper(); private static Hashtable _propertyTable; // key=DP, data=listener count #endregion Private Fields } } // 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
- RequestBringIntoViewEventArgs.cs
- TraceContextEventArgs.cs
- XmlSchemaObjectTable.cs
- SaveFileDialog.cs
- Message.cs
- TextWriter.cs
- VScrollProperties.cs
- SamlNameIdentifierClaimResource.cs
- SelectionProcessor.cs
- Cursor.cs
- MultipleViewPattern.cs
- MessageContractMemberAttribute.cs
- DoubleAverageAggregationOperator.cs
- SecurityKeyUsage.cs
- BaseDataListDesigner.cs
- ListBoxItemAutomationPeer.cs
- DesignerDataTableBase.cs
- CompensationExtension.cs
- ImageMap.cs
- ExceptionHelpers.cs
- ComboBox.cs
- Classification.cs
- RowToFieldTransformer.cs
- DateTimeConverter2.cs
- AppModelKnownContentFactory.cs
- DockAndAnchorLayout.cs
- GPRECTF.cs
- IndexExpression.cs
- Matrix3D.cs
- XmlDataProvider.cs
- NameSpaceExtractor.cs
- DataControlLinkButton.cs
- GridViewRow.cs
- DrawingGroup.cs
- HuffCodec.cs
- StylusShape.cs
- COM2ColorConverter.cs
- CodeDomDecompiler.cs
- Binding.cs
- SimpleWebHandlerParser.cs
- X509ChainPolicy.cs
- XmlUnspecifiedAttribute.cs
- SafeTimerHandle.cs
- TargetException.cs
- RootNamespaceAttribute.cs
- GeneralTransform3DGroup.cs
- DesignerObject.cs
- BackgroundWorker.cs
- CompilerCollection.cs
- WebReferenceOptions.cs
- UnauthorizedWebPart.cs
- TableRowGroupCollection.cs
- MsmqChannelListenerBase.cs
- HttpDictionary.cs
- XPathAncestorIterator.cs
- IsolatedStorage.cs
- ExpressionBuilderContext.cs
- ContentPlaceHolder.cs
- BrowserCapabilitiesFactory.cs
- SetMemberBinder.cs
- VerificationAttribute.cs
- ScrollBarAutomationPeer.cs
- SqlPersonalizationProvider.cs
- IPAddressCollection.cs
- PropVariant.cs
- contentDescriptor.cs
- PathTooLongException.cs
- BitmapEffectRenderDataResource.cs
- PkcsUtils.cs
- SchemaDeclBase.cs
- HttpWebRequest.cs
- ValidationRuleCollection.cs
- RegistrationServices.cs
- LayoutTableCell.cs
- GcHandle.cs
- CssTextWriter.cs
- SectionXmlInfo.cs
- CollectionType.cs
- TaskScheduler.cs
- DtcInterfaces.cs
- ArgumentNullException.cs
- IconHelper.cs
- ZipIORawDataFileBlock.cs
- MetadataArtifactLoaderCompositeResource.cs
- CfgArc.cs
- LocalBuilder.cs
- Filter.cs
- CombinedGeometry.cs
- StringFunctions.cs
- XmlNamedNodeMap.cs
- SamlSerializer.cs
- WindowsGraphics.cs
- CodeVariableReferenceExpression.cs
- DataRowView.cs
- Trace.cs
- CodePageEncoding.cs
- BitmapEffect.cs
- OLEDB_Enum.cs
- Bookmark.cs
- AnimatedTypeHelpers.cs