Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Framework / MS / Internal / Controls / ModelTreeEnumerator.cs / 1305600 / ModelTreeEnumerator.cs
//---------------------------------------------------------------------------- // //// Copyright (C) Microsoft Corporation. All rights reserved. // // //--------------------------------------------------------------------------- using System; using System.Collections; using System.ComponentModel; using System.Diagnostics; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using MS.Internal.Controls; using MS.Internal.Data; using MS.Utility; namespace MS.Internal.Controls { internal abstract class ModelTreeEnumerator : IEnumerator { internal ModelTreeEnumerator(object content) { _content = content; } #region IEnumerator object IEnumerator.Current { get { return this.Current; } } bool IEnumerator.MoveNext() { return this.MoveNext(); } void IEnumerator.Reset() { this.Reset(); } #endregion #region Protected protected object Content { get { return _content; } } protected int Index { get { return _index; } set { _index = value; } } protected virtual object Current { get { // Don't VerifyUnchanged(); According to MSDN: // If the collection is modified between MoveNext and Current, // Current will return the element that it is set to, even if // the enumerator is already invalidated. if (_index == 0) { return _content; } #pragma warning disable 1634 // about to use PreSharp message numbers - unknown to C# // Fall through -- can't enumerate (before beginning or after end) #pragma warning suppress 6503 throw new InvalidOperationException(SR.Get(SRID.EnumeratorInvalidOperation)); // above exception is part of the IEnumerator.Current contract when moving beyond begin/end #pragma warning restore 1634 } } protected virtual bool MoveNext() { if (_index < 1) { // Singular content, can move next to 0 and that's it. _index++; if (_index == 0) { // don't call VerifyUnchanged if we're returning false anyway. // This permits users to change the Content after enumerating // the content (e.g. in the invalidation callback of an inherited // property). See bug 955389. VerifyUnchanged(); return true; } } return false; } protected virtual void Reset() { VerifyUnchanged(); _index = -1; } protected abstract bool IsUnchanged { get; } protected void VerifyUnchanged() { // If the content has changed, then throw an exception if (!IsUnchanged) { throw new InvalidOperationException(SR.Get(SRID.EnumeratorVersionChanged)); } } #endregion #region Data private int _index = -1; private object _content; #endregion } internal class ContentModelTreeEnumerator : ModelTreeEnumerator { internal ContentModelTreeEnumerator(ContentControl contentControl, object content) : base(content) { Debug.Assert(contentControl != null, "contentControl should be non-null."); _owner = contentControl; } protected override bool IsUnchanged { get { return Object.ReferenceEquals(Content, _owner.Content); } } private ContentControl _owner; } internal class HeaderedContentModelTreeEnumerator : ModelTreeEnumerator { internal HeaderedContentModelTreeEnumerator(HeaderedContentControl headeredContentControl, object content, object header) : base(header) { Debug.Assert(headeredContentControl != null, "headeredContentControl should be non-null."); Debug.Assert(header != null, "Header should be non-null. If Header was null, the base ContentControl enumerator should have been used."); _owner = headeredContentControl; _content = content; } protected override object Current { get { if ((Index == 1) && (_content != null)) { return _content; } return base.Current; } } protected override bool MoveNext() { if (_content != null) { if (Index == 0) { // Moving from the header to content Index++; VerifyUnchanged(); return true; } else if (Index == 1) { // Going from content to the end Index++; return false; } } return base.MoveNext(); } protected override bool IsUnchanged { get { object header = Content; // Header was passed to the base so that it would appear in index 0 return Object.ReferenceEquals(header, _owner.Header) && Object.ReferenceEquals(_content, _owner.Content); } } private HeaderedContentControl _owner; private object _content; } internal class HeaderedItemsModelTreeEnumerator : ModelTreeEnumerator { internal HeaderedItemsModelTreeEnumerator(HeaderedItemsControl headeredItemsControl, IEnumerator items, object header) : base(header) { Debug.Assert(headeredItemsControl != null, "headeredItemsControl should be non-null."); Debug.Assert(items != null, "items should be non-null."); Debug.Assert(header != null, "header should be non-null. If Header was null, the base ItemsControl enumerator should have been used."); _owner = headeredItemsControl; _items = items; } protected override object Current { get { if (Index > 0) { return _items.Current; } return base.Current; } } protected override bool MoveNext() { if (Index >= 0) { Index++; return _items.MoveNext(); } return base.MoveNext(); } protected override void Reset() { base.Reset(); _items.Reset(); } protected override bool IsUnchanged { get { object header = Content; // Header was passed to the base so that it would appear in index 0 return Object.ReferenceEquals(header, _owner.Header); } } private HeaderedItemsControl _owner; private IEnumerator _items; } } // 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
- NativeWrapper.cs
- RequestContext.cs
- DynamicRendererThreadManager.cs
- GenericsNotImplementedException.cs
- MenuBindingsEditorForm.cs
- RSACryptoServiceProvider.cs
- _TransmitFileOverlappedAsyncResult.cs
- ScriptingSectionGroup.cs
- VarInfo.cs
- Metafile.cs
- TraceUtils.cs
- CompositionAdorner.cs
- NotFiniteNumberException.cs
- TrackingMemoryStream.cs
- GridLength.cs
- ContentPropertyAttribute.cs
- Permission.cs
- PassportAuthenticationModule.cs
- QilValidationVisitor.cs
- SafeSystemMetrics.cs
- XmlBindingWorker.cs
- XmlHierarchyData.cs
- CatalogPart.cs
- Main.cs
- ComponentFactoryHelpers.cs
- ParameterRetriever.cs
- ChtmlPageAdapter.cs
- JulianCalendar.cs
- DataGridViewColumnConverter.cs
- WindowsContainer.cs
- Soap12FormatExtensions.cs
- SelectQueryOperator.cs
- RegexCompiler.cs
- RefreshResponseInfo.cs
- StateMachineWorkflowInstance.cs
- SqlLiftWhereClauses.cs
- NotificationContext.cs
- InvalidPipelineStoreException.cs
- CodeExporter.cs
- LogEntryDeserializer.cs
- MsmqProcessProtocolHandler.cs
- InternalTransaction.cs
- WindowsListView.cs
- SessionViewState.cs
- GZipDecoder.cs
- NetDataContractSerializer.cs
- TemplateXamlParser.cs
- ProxyAttribute.cs
- configsystem.cs
- ModuleConfigurationInfo.cs
- ModifyActivitiesPropertyDescriptor.cs
- SqlMultiplexer.cs
- StateElement.cs
- WebPartDisplayModeCollection.cs
- ProtectedUri.cs
- TraceSwitch.cs
- Converter.cs
- SpecularMaterial.cs
- MessageLoggingElement.cs
- JsonReader.cs
- VideoDrawing.cs
- BitmapCache.cs
- AllowedAudienceUriElementCollection.cs
- TextBox.cs
- QueryComponents.cs
- ProviderIncompatibleException.cs
- RichTextBox.cs
- UdpConstants.cs
- UniqueEventHelper.cs
- SetIterators.cs
- FixedSOMPageElement.cs
- WpfKnownType.cs
- XmlSchemaInfo.cs
- CodeSnippetCompileUnit.cs
- CheckBoxField.cs
- RotateTransform3D.cs
- ModelTreeEnumerator.cs
- WeakEventManager.cs
- OperationExecutionFault.cs
- WebPartDescription.cs
- OleDbRowUpdatingEvent.cs
- WsatConfiguration.cs
- CompModHelpers.cs
- AlternateViewCollection.cs
- DataGridState.cs
- DuplexChannel.cs
- QueueSurrogate.cs
- RawStylusInputCustomDataList.cs
- MimeObjectFactory.cs
- GridEntryCollection.cs
- ThreadInterruptedException.cs
- SmtpCommands.cs
- SynchronizationValidator.cs
- ThicknessAnimationUsingKeyFrames.cs
- MSAAEventDispatcher.cs
- TableRow.cs
- EntityDataSourceEntityTypeFilterConverter.cs
- SiteMapNodeCollection.cs
- BinHexEncoding.cs
- WorkflowApplicationEventArgs.cs