Code:
/ FXUpdate3074 / FXUpdate3074 / 1.1 / untmp / whidbey / QFE / ndp / fx / src / xsp / System / Web / UI / WebControls / CompositeDataBoundControl.cs / 2 / CompositeDataBoundControl.cs
//------------------------------------------------------------------------------ //// Copyright (c) Microsoft Corporation. All rights reserved. // //----------------------------------------------------------------------------- namespace System.Web.UI.WebControls { using System; using System.Collections; using System.Security.Permissions; [AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)] [AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)] public abstract class CompositeDataBoundControl : DataBoundControl, INamingContainer { internal const string ItemCountViewStateKey = "_!ItemCount"; public override ControlCollection Controls { get { EnsureChildControls(); return base.Controls; } } ////// Overriden by DataBoundControl to determine if the control should /// recreate its control hierarchy based on values in view state. /// If the control hierarchy should be created, i.e. view state does /// exist, it calls CreateChildControls with a dummy (empty) data source /// which is usable for enumeration purposes only. /// protected internal override void CreateChildControls() { Controls.Clear(); object controlCount = ViewState[ItemCountViewStateKey]; if (controlCount == null && RequiresDataBinding) { EnsureDataBound(); } if (controlCount != null && ((int)controlCount) != -1) { DummyDataSource dummyDataSource = new DummyDataSource((int)controlCount); CreateChildControls(dummyDataSource, false); ClearChildViewState(); } } ////// Performs the work of creating the control hierarchy based on a data source. /// When dataBinding is true, the specified data source contains real /// data, and the data is supposed to be pushed into the UI. /// When dataBinding is false, the specified data source is a dummy data /// source, that allows enumerating the right number of items, but the items /// themselves are null and do not contain data. In this case, the recreated /// control hierarchy reinitializes its state from view state. /// It enables a DataBoundControl to encapsulate the logic of creating its /// control hierarchy in both modes into a single code path. /// /// /// The data source to be used to enumerate items. /// /// /// Whether the method has been called from DataBind or not. /// ////// The number of items created based on the data source. Put another way, its /// the number of items enumerated from the data source. /// protected abstract int CreateChildControls(IEnumerable dataSource, bool dataBinding); ////// Overriden by DataBoundControl to use its properties to determine the real /// data source that the control should bind to. It then clears the existing /// control hierarchy, and calls createChildControls to create a new control /// hierarchy based on the resolved data source. /// The implementation resolves various data source related properties to /// arrive at the appropriate IEnumerable implementation to use as the real /// data source. /// When resolving data sources, the DataSourceControlID takes highest precedence. /// In this mode, DataMember is used to access the appropriate list from the /// DataControl. /// If DataSourceControlID is not set, the value of the DataSource property is used. /// In this second alternative, DataMember is used to extract the appropriate /// list if the control has been handed an IListSource as a data source. /// protected internal override void PerformDataBinding(IEnumerable data) { base.PerformDataBinding(data); Controls.Clear(); ClearChildViewState(); TrackViewState(); int controlCount = CreateChildControls(data, true); ChildControlsCreated = true; ViewState[ItemCountViewStateKey] = controlCount; } } } // 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
- IdentitySection.cs
- ICspAsymmetricAlgorithm.cs
- ResourceType.cs
- WindowsGraphicsCacheManager.cs
- State.cs
- arabicshape.cs
- RegexWriter.cs
- Margins.cs
- ServiceMemoryGates.cs
- StackOverflowException.cs
- KeyedQueue.cs
- ArgumentOutOfRangeException.cs
- HealthMonitoringSectionHelper.cs
- DataGridViewRowCancelEventArgs.cs
- Rectangle.cs
- WindowsAltTab.cs
- RuntimeIdentifierPropertyAttribute.cs
- DropShadowBitmapEffect.cs
- UpDownBase.cs
- GregorianCalendarHelper.cs
- lengthconverter.cs
- ItemType.cs
- DiscoveryMessageSequence11.cs
- VScrollBar.cs
- __ComObject.cs
- WebPartMenu.cs
- WebPartChrome.cs
- VectorKeyFrameCollection.cs
- WebBrowsableAttribute.cs
- TableCellCollection.cs
- Base64Stream.cs
- TimeBoundedCache.cs
- SqlUnionizer.cs
- Identity.cs
- Stroke.cs
- XmlLinkedNode.cs
- TextEditorParagraphs.cs
- OleTxTransactionInfo.cs
- AnnotationAdorner.cs
- CodeGroup.cs
- XmlSchemaExternal.cs
- AttributeCollection.cs
- BaseTemplateCodeDomTreeGenerator.cs
- CellTreeSimplifier.cs
- ServerValidateEventArgs.cs
- TextElementEnumerator.cs
- HttpContextBase.cs
- CustomUserNameSecurityTokenAuthenticator.cs
- CompoundFileIOPermission.cs
- DateTimeStorage.cs
- localization.cs
- GridViewRowPresenterBase.cs
- QueryOutputWriter.cs
- _TransmitFileOverlappedAsyncResult.cs
- ContractMethodInfo.cs
- NoneExcludedImageIndexConverter.cs
- StatusBarDrawItemEvent.cs
- ObjectStateManager.cs
- ZipIOExtraField.cs
- XNodeValidator.cs
- OperationContext.cs
- GridSplitterAutomationPeer.cs
- CodeTypeDeclarationCollection.cs
- PixelFormatConverter.cs
- SqlException.cs
- WorkflowPrinting.cs
- CommandDevice.cs
- ChildrenQuery.cs
- ForAllOperator.cs
- SafeArrayRankMismatchException.cs
- TransformFinalBlockRequest.cs
- BamlBinaryReader.cs
- HierarchicalDataBoundControlAdapter.cs
- QuadraticBezierSegment.cs
- FormViewInsertEventArgs.cs
- QueryInterceptorAttribute.cs
- SafeThreadHandle.cs
- DES.cs
- Mapping.cs
- MetadataUtilsSmi.cs
- TextMessageEncoder.cs
- DefaultShape.cs
- DocumentViewer.cs
- XmlReaderDelegator.cs
- DeferrableContent.cs
- SoapExtension.cs
- SharedConnectionInfo.cs
- PageClientProxyGenerator.cs
- WebServiceData.cs
- ConfigUtil.cs
- SqlTriggerContext.cs
- XD.cs
- EntryPointNotFoundException.cs
- X509Certificate2.cs
- KnownBoxes.cs
- ScrollBarRenderer.cs
- SrgsSemanticInterpretationTag.cs
- NewExpression.cs
- WindowCollection.cs
- GPRECTF.cs