Code:
/ DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / WinForms / Managed / System / WinForms / HtmlShim.cs / 1 / HtmlShim.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //----------------------------------------------------------------------------- namespace System.Windows.Forms { using System; using System.Collections.Generic; using System.ComponentModel; using System.Diagnostics.CodeAnalysis; /// This is essentially a proxy object between the native /// html objects and our managed ones. We want the managed /// HtmlDocument, HtmlWindow and HtmlElement to be super-lightweight, /// which means that we shouldnt have things that tie up their lifetimes /// contained within them. The "Shim" is essentially the object that /// manages events coming out of the HtmlDocument, HtmlElement and HtmlWindow /// and serves them back up to the user. internal abstract class HtmlShim : IDisposable { private EventHandlerList events; private int eventCount = 0; private DictionaryattachedEventList; protected HtmlShim() { } ~HtmlShim() { Dispose(false); } private EventHandlerList Events { get { if (events == null) { events = new EventHandlerList(); } return events; } } /// Support IHtml*3.AttachHandler public abstract void AttachEventHandler(string eventName, EventHandler eventHandler); public void AddHandler(object key, Delegate value) { eventCount++; Events.AddHandler(key, value); OnEventHandlerAdded(); } protected HtmlToClrEventProxy AddEventProxy(string eventName, EventHandler eventHandler) { if (attachedEventList == null) { attachedEventList = new Dictionary (); } HtmlToClrEventProxy proxy = new HtmlToClrEventProxy(this, eventName, eventHandler); attachedEventList[eventHandler] = proxy; return proxy; } public abstract UnsafeNativeMethods.IHTMLWindow2 AssociatedWindow { get; } /// create connectionpoint cookie public abstract void ConnectToEvents(); /// Support IHtml*3.DetachEventHandler public abstract void DetachEventHandler(string eventName, EventHandler eventHandler); /// disconnect from connectionpoint cookie /// inheriting classes should override to disconnect from ConnectionPoint and call base. public virtual void DisconnectFromEvents() { if (attachedEventList != null) { EventHandler[] events = new EventHandler[attachedEventList.Count]; attachedEventList.Keys.CopyTo(events,0); foreach (EventHandler eh in events) { HtmlToClrEventProxy proxy = attachedEventList[eh]; DetachEventHandler(proxy.EventName, eh); } } } /// return the sender for events, usually the HtmlWindow, HtmlElement, HtmlDocument protected abstract object GetEventSender(); public void Dispose() { Dispose(true); GC.SuppressFinalize(this); } protected virtual void Dispose(bool disposing) { if (disposing) { DisconnectFromEvents(); if (this.events != null) { this.events.Dispose(); this.events = null; } } } public void FireEvent(object key, EventArgs e) { System.Delegate delegateToInvoke = (System.Delegate)Events[key]; if (delegateToInvoke != null) { try { delegateToInvoke.DynamicInvoke(GetEventSender(), e); } catch (Exception ex) { // Note: this check is for the debugger, so we can catch exceptions in the debugger instead of // throwing a thread exception. if (NativeWindow.WndProcShouldBeDebuggable) { throw; } else { Application.OnThreadException(ex); } } } } protected virtual void OnEventHandlerAdded() { ConnectToEvents(); } protected virtual void OnEventHandlerRemoved() { if (eventCount <=0) { DisconnectFromEvents(); eventCount = 0; } } public void RemoveHandler(object key, Delegate value) { eventCount--; Events.RemoveHandler(key, value); OnEventHandlerRemoved(); } protected HtmlToClrEventProxy RemoveEventProxy(EventHandler eventHandler) { if (attachedEventList == null) { return null; } if (attachedEventList.ContainsKey(eventHandler)) { HtmlToClrEventProxy proxy = attachedEventList[eventHandler] as HtmlToClrEventProxy; attachedEventList.Remove(eventHandler); return proxy; } return null; } } } // 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
- ColumnHeaderConverter.cs
- ConnectionManagementElement.cs
- ClientData.cs
- BrowserCapabilitiesFactoryBase.cs
- CompositeScriptReference.cs
- PropertyReferenceSerializer.cs
- PopupRoot.cs
- Gdiplus.cs
- QueryOptionExpression.cs
- ScrollableControlDesigner.cs
- MessageQueueInstaller.cs
- ThreadStaticAttribute.cs
- OleDbRowUpdatedEvent.cs
- InvalidOperationException.cs
- DataObjectMethodAttribute.cs
- Documentation.cs
- HierarchicalDataSourceControl.cs
- SoapIgnoreAttribute.cs
- UriTemplateLiteralQueryValue.cs
- CodeTypeDelegate.cs
- MsmqAppDomainProtocolHandler.cs
- DataGridColumnCollection.cs
- FontFamilyConverter.cs
- ConstructorBuilder.cs
- DataGridViewEditingControlShowingEventArgs.cs
- DuplicateWaitObjectException.cs
- FixUp.cs
- DispatchWrapper.cs
- WebResourceAttribute.cs
- LifetimeServices.cs
- Menu.cs
- UnsafeNetInfoNativeMethods.cs
- SessionPageStateSection.cs
- PropertyInformation.cs
- FileSystemEventArgs.cs
- DivideByZeroException.cs
- OutOfProcStateClientManager.cs
- SimpleBitVector32.cs
- ControlParameter.cs
- NativeMethods.cs
- StringAttributeCollection.cs
- TemplateInstanceAttribute.cs
- DateTimeValueSerializer.cs
- HttpCacheParams.cs
- ShaderRenderModeValidation.cs
- HtmlHead.cs
- XmlCompatibilityReader.cs
- CmsInterop.cs
- ErrorProvider.cs
- GridViewUpdateEventArgs.cs
- IndexedString.cs
- WebPartCancelEventArgs.cs
- Attributes.cs
- BindingList.cs
- DbConnectionFactory.cs
- isolationinterop.cs
- DistributedTransactionPermission.cs
- KeyEventArgs.cs
- MultitargetingHelpers.cs
- ObjectIDGenerator.cs
- SQLUtility.cs
- CheckBoxBaseAdapter.cs
- SqlPersonalizationProvider.cs
- SmtpClient.cs
- SpellerInterop.cs
- ResourceDescriptionAttribute.cs
- DaylightTime.cs
- AssociationEndMember.cs
- UpdatePanel.cs
- SizeConverter.cs
- ColorKeyFrameCollection.cs
- SessionPageStateSection.cs
- SqlDataSourceTableQuery.cs
- NativeMethods.cs
- DrawingAttributesDefaultValueFactory.cs
- WpfWebRequestHelper.cs
- Transform3D.cs
- TextElementAutomationPeer.cs
- ScrollItemPattern.cs
- DictionaryBase.cs
- BaseTemplatedMobileComponentEditor.cs
- AccessViolationException.cs
- CultureTableRecord.cs
- StickyNote.cs
- CodeAttributeArgumentCollection.cs
- RegistryConfigurationProvider.cs
- XmlDocument.cs
- IPAddressCollection.cs
- BamlTreeMap.cs
- MenuItemStyleCollectionEditor.cs
- CellTreeNodeVisitors.cs
- HttpWebResponse.cs
- WebResourceUtil.cs
- BackgroundWorker.cs
- FlatButtonAppearance.cs
- EdmScalarPropertyAttribute.cs
- FormViewDeleteEventArgs.cs
- ComEventsSink.cs
- StickyNote.cs
- PropertySegmentSerializationProvider.cs