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
- ComboBoxRenderer.cs
- ComAdminWrapper.cs
- DataServiceQueryProvider.cs
- AmbiguousMatchException.cs
- CodeDirectiveCollection.cs
- ToolStripArrowRenderEventArgs.cs
- MaterializeFromAtom.cs
- AutoResetEvent.cs
- SafeJobHandle.cs
- AlphabeticalEnumConverter.cs
- GetLedgerEntryForRecipientRequest.cs
- TextParagraphProperties.cs
- DispatcherSynchronizationContext.cs
- PropertyGrid.cs
- ContextMenuService.cs
- Function.cs
- KoreanCalendar.cs
- PathTooLongException.cs
- CollaborationHelperFunctions.cs
- PerspectiveCamera.cs
- DataSourceView.cs
- PhysicalFontFamily.cs
- WebPartPersonalization.cs
- ImageFormat.cs
- HideDisabledControlAdapter.cs
- TcpServerChannel.cs
- ComponentChangedEvent.cs
- XmlUrlResolver.cs
- Slider.cs
- SmiXetterAccessMap.cs
- MailAddressCollection.cs
- ApplicationDirectoryMembershipCondition.cs
- columnmapkeybuilder.cs
- dbdatarecord.cs
- Compiler.cs
- ProtocolsConfigurationEntry.cs
- RsaSecurityToken.cs
- ToolBarPanel.cs
- latinshape.cs
- CustomLineCap.cs
- TcpAppDomainProtocolHandler.cs
- DtrList.cs
- BaseConfigurationRecord.cs
- FormViewInsertEventArgs.cs
- MaterialCollection.cs
- Encoder.cs
- ProxyAttribute.cs
- AmbientValueAttribute.cs
- OleDbStruct.cs
- XmlILIndex.cs
- TextTreeInsertUndoUnit.cs
- ValueHandle.cs
- Image.cs
- SqlFileStream.cs
- CopyOnWriteList.cs
- CodeNamespaceImportCollection.cs
- InvokeWebServiceDesigner.cs
- ConstNode.cs
- ToolboxItemAttribute.cs
- AnonymousIdentificationSection.cs
- DirectionalLight.cs
- Stack.cs
- FlowLayoutPanel.cs
- TextServicesHost.cs
- AsyncCodeActivity.cs
- BinaryFormatterWriter.cs
- LineSegment.cs
- HasCopySemanticsAttribute.cs
- NameValueSectionHandler.cs
- _TransmitFileOverlappedAsyncResult.cs
- WebPartVerbsEventArgs.cs
- SmtpAuthenticationManager.cs
- LayoutEditorPart.cs
- WebRequestModuleElementCollection.cs
- XmlDeclaration.cs
- InputLangChangeRequestEvent.cs
- QilStrConcatenator.cs
- JournalEntryListConverter.cs
- counter.cs
- CustomUserNameSecurityTokenAuthenticator.cs
- ToolboxBitmapAttribute.cs
- FlowDocument.cs
- BitmapCache.cs
- QuadraticBezierSegment.cs
- XComponentModel.cs
- PathParser.cs
- ExpressionNode.cs
- ExpressionConverter.cs
- PoisonMessageException.cs
- safex509handles.cs
- MimeTypePropertyAttribute.cs
- PrintDialogDesigner.cs
- StylusSystemGestureEventArgs.cs
- StringFormat.cs
- MenuItemStyle.cs
- ImageButton.cs
- CompoundFileStorageReference.cs
- InputProviderSite.cs
- NumberEdit.cs
- DbConnectionClosed.cs