System.Web.UI Namespace

This namespace includes the Control class, which provides a common set of functionality for all server controls, which includes HTML server controls, Web server controls, and user controls. It also includes the Page class. This class is generated automatically whenever a request is made for an .aspx file in an ASP.NET Web application. You can inherit from both of these classes.

The namespace also includes classes that provide the server controls with data-binding functionality, the ability to save the view state of a given control or page, and parsing functionality.

Classes

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	Class	Description
	AsyncPostBackErrorEventArgs	Provides data for the AsyncPostBackError event.
	AsyncPostBackTrigger	Defines a control and optional event of the control as an asynchronous postback control trigger that causes an UpdatePanel control to refresh.
	AttributeCollection	Provides object-model access to all attributes declared in the opening tag of an ASP.NET server control element. This class cannot be inherited.
	AuthenticationServiceManager	Configures the location of a custom implementation of the authentication service.
	BaseParser	Provides a base set of functionality for classes involved in parsing ASP.NET page requests and server controls.
	BasePartialCachingControl	Provides the base functionality for the StaticPartialCachingControl and PartialCachingControl classes.
	BaseTemplateParser	Infrastructure. Implements ASP.NET template parsing for template files.
	BindableTemplateBuilder	Supports page parsing of data-bound controls that automatically bind to an ASP.NET data source control within templated content sections. This class cannot be inherited.
	BoundPropertyEntry	Infrastructure. Represents a control property that is data-bound to an expression.
	BuilderPropertyEntry	Serves as the base class for all property entries that require a control builder.
	ChtmlTextWriter	Writes a series of cHTML-specific characters and text to the output stream of an ASP.NET server control. The ChtmlTextWriter class provides formatting capabilities that ASP.NET server controls use when rendering cHTML content to clients.
	ClientScriptManager	Defines methods for managing client scripts in Web applications.
	CompiledBindableTemplateBuilder	Infrastructure. Provides the default implementation of an IBindableTemplate object, which ASP.NET uses whenever it parses two-way data-binding within the templated content of an ASP.NET control such as FormView. This class cannot be inherited.
	CompiledTemplateBuilder	Infrastructure. An ITemplate implementation that is called from the generated page class code. This class cannot be inherited.
	ComplexPropertyEntry	Infrastructure. Serves as the property entry for read/write and read-only properties such as templates.
	CompositeScriptReference	Represents a collection of script references to combine into a single composite script.
	CompositeScriptReferenceEventArgs	Provides data for the ResolveCompositeScriptReference event.
	ConstructorNeedsTagAttribute	Specifies that a server control needs a tag name in its constructor.
	Control	Defines the properties, methods, and events that are shared by all ASP.NET server controls.
	ControlBuilder	Supports the page parser in building a control and the child controls it contains.
	ControlBuilderAttribute	Specifies a ControlBuilder class for building a custom control within the ASP.NET parser. This class cannot be inherited.
	ControlCachePolicy	Provides programmatic access to an ASP.NET user control's output cache settings.
	ControlCollection	Provides a collection container that enables ASP.NET server controls to maintain a list of their child controls.
	ControlSkin	Represents a control skin, which is a means to define stylistic properties that are applied to an ASP.NET Web server control.
	ControlValuePropertyAttribute	Specifies the default property of a control that a ControlParameter object binds to at run time. This class cannot be inherited.
	CssClassPropertyAttribute	Adds Cascading Style Sheet (CSS) editing capabilities to a property at design time.
	CssStyleCollection	Contains the HTML cascading-style sheets (CSS) inline style attributes for a specified HTML server control. This class cannot be inherited.
	DataBinder	Provides support for rapid application development (RAD) designers to generate and parse data-binding expression syntax. This class cannot be inherited.
	DataBinding	Contains information about a single data-binding expression in an ASP.NET server control, which allows rapid-application development (RAD) designers, such as Microsoft Visual Studio, to create data-binding expressions at design time. This class cannot be inherited.
	DataBindingCollection	Provides a collection of DataBinding objects for an ASP.NET server control. This class cannot be inherited.
	DataBindingHandlerAttribute	Specifies a design-time class that performs data binding of controls within a designer. This class cannot be inherited.
	DataBoundLiteralControl	Retains data-binding expressions and static literal text. This class cannot be inherited.
	DataSourceCacheDurationConverter	Provides a type converter to convert 32-bit signed integer objects to and from data source control cache duration representations.
	DataSourceControl	Serves as the base class for controls that represent data sources to data-bound controls.
	DataSourceControlBuilder	Supports the page parser in building controls that are connected to a data provider. This class cannot be inherited.
	DataSourceSelectArguments	Provides a mechanism that data-bound controls use to request data-related operations from data source controls when data is retrieved. This class cannot be inherited.
	DataSourceView	Serves as the base class for all data source view classes, which define the capabilities of data source controls.
	DesignerDataBoundLiteralControl	Infrastructure. Represents the design-time version of the DataBoundLiteralControl control. This class cannot be inherited.
	DesignTimeParseData	Infrastructure. Provides information to the parser during design time.
	DesignTimeTemplateParser	Infrastructure. Provides parsing at design time.
	EmptyControlCollection	Provides standard support for a ControlCollection collection that is always empty.
	EventEntry	Infrastructure. Acts as the property entry for event handlers.
	ExpressionBinding	Infrastructure. Supports the parsing and persisting of an expression-binding instance. This class cannot be inherited.
	ExpressionBindingCollection	Infrastructure. Represents a collection of ExpressionBinding objects. This class cannot be inherited.
	ExtenderControl	Provides an abstract base class for an extender control.
	FileLevelControlBuilderAttribute	Allows a TemplateControl-derived class to specify the control builder used at the top level of the builder tree when parsing the file. This class cannot be inherited.
	FileLevelPageControlBuilder	Parses page files and is the default ControlBuilder class for parsing page files.
	FileLevelUserControlBuilder	Supports the page parser in building a user control by specifying the FileLevelUserControlBuilder class that is used to parse the user control file.
	FilterableAttribute	Specifies whether the property to which the attribute is applied supports device filtering. This class cannot be inherited.
	HiddenFieldPageStatePersister	Stores ASP.NET page view state on the Web client in a hidden HTML element.
	HierarchicalDataSourceControl	Provides a base class for data source controls that represent hierarchical data.
	HierarchicalDataSourceView	Represents a data view on a node or collection of nodes in a hierarchical data structure for a HierarchicalDataSourceControl control.
	HistoryEventArgs	Provides data for the Navigate event.
	Html32TextWriter	Writes a series of HTML 3.2–specific characters and text to the output stream for an ASP.NET server control. The Html32TextWriter class provides formatting capabilities that ASP.NET server controls use when rendering HTML 3.2 content to clients.
	HtmlTextWriter	Writes markup characters and text to an ASP.NET server control output stream. This class provides formatting capabilities that ASP.NET server controls use when rendering markup to clients.
	IDReferencePropertyAttribute	Defines an attribute applied to properties that contain ID references. This class cannot be inherited.
	ImageClickEventArgs	Provides data for any events that occur when a user clicks an image-based ASP.NET server control, such as the HtmlInputImage or ImageButton server controls. This class cannot be inherited.
	IndexedString	Provides a utility string class that is used by the ObjectStateFormatter class to optimize object graph serialization. This class cannot be inherited.
	ListSourceHelper	Used by data source controls when implementing the members defined by the IListSource interface. This class cannot be inherited.
	LiteralControl	Represents HTML elements, text, and any other strings in an ASP.NET page that do not require processing on the server.
	LosFormatter	Serializes the view state for a Web Forms page. This class cannot be inherited.
	MasterPage	Acts as a template and merging container for pages that are composed only of Content controls and their respective child controls.
	MasterPageControlBuilder	Acts as a merging class and container for content pages that are composed only of Content controls and their respective child controls.
	NonVisualControlAttribute	Defines the attribute that indicates whether a control is treated as a visual or non-visual control during design time. This class cannot be inherited.
	ObjectConverter	Infrastructure. Obsolete. Converts an object from one object type to another object type. This class is obsolete. Use the Convert class and the Format method instead.
	ObjectPersistData	Infrastructure. During the build process, retains information about property entries.
	ObjectStateFormatter	Serializes and deserializes object graphs that represent the state of an object. This class cannot be inherited.
	ObjectTagBuilder	Infrastructure. Used by the ASP.NET TemplateParser class to parse server-side <object> tags. This class can not be inherited.
	OutputCacheParameters	Encapsulates the output cache initialization settings parsed from an @ OutputCache page directive by ASP.NET. This class cannot be inherited.
	Page	Represents an .aspx file, also known as a Web Forms page, requested from a server that hosts an ASP.NET Web application.
	PageAsyncTask	Contains information about an asynchronous task registered to a page. This class cannot be inherited.
	PageHandlerFactory	Creates instances of classes that inherit from the Page class and implement the IHttpHandler interface. Instances are created dynamically to handle requests for ASP.NET files. The PageHandlerFactory class is the default handler factory implementation for ASP.NET pages.
	PageParser	Infrastructure. Implements a parser for .aspx files. This class cannot be inherited.
	PageParserFilter	Provides an abstract base class for a page parser filter that is used by the ASP.NET parser to determine whether an item is allowed in the page at parse time.
	PageStatePersister	Provides the base functionality for ASP.NET view state persistence mechanisms.
	PageTheme	Represents the base class for a page theme, which is a collection of resources that are used to define a consistent look across pages and controls in a Web site. The page theme can be set through configuration or the page directive.
	Pair	Provides a basic utility class that is used to store two related objects.
	ParseChildrenAttribute	Defines a metadata attribute that you can use when developing ASP.NET server controls. Use the ParseChildrenAttribute class to indicate how the page parser should treat content nested inside a server control tag declared on a page. This class cannot be inherited.
	PartialCachingAttribute	Defines the metadata attribute that Web Forms user controls (.ascx files) use to indicate if and how their output is cached. This class cannot be inherited.
	PartialCachingControl	Created when a user control (.ascx file) is specified for output caching, using either the @ OutputCache page directive or the PartialCachingAttribute attribute, and the user control is inserted into a page's control hierarchy by dynamically loading the user control with the TemplateControl::LoadControl method.
	PersistChildrenAttribute	Defines an attribute that is used by ASP.NET server controls to indicate at design time whether nested content that is contained within a server control corresponds to controls or to properties of the server control. This class cannot be inherited.
	PersistenceModeAttribute	Defines the metadata attribute that specifies how an ASP.NET server control property or event is persisted to an ASP.NET page at design time. This class cannot be inherited.
	PostBackOptions	Specifies how client-side JavaScript is generated to initiate a postback event.
	PostBackTrigger	Defines a control inside a UpdatePanel control as a postback control.
	ProfileServiceManager	Configures a set of preloaded profile properties and the location of a custom implementation of the profile service.
	PropertyConverter	Infrastructure. Contains helper functions to convert property values to and from strings.
	PropertyEntry	Infrastructure. Acts as the base class for all property entry classes.
	RegisteredArrayDeclaration	Provides access to an ECMAScript (JavaScript) array declaration that was previously registered with the Page object.
	RegisteredDisposeScript	Provides access to a dispose script for a control that is inside an UpdatePanel control.
	RegisteredExpandoAttribute	Provides access to the name/value pair of a custom (expando) attribute that was previously registered with the Page object.
	RegisteredHiddenField	Provides access to a hidden value that was previously registered with the Page object.
	RegisteredScript	Provides access to a client script that was previously registered with the Page object.
	RoleServiceManager	Configures the location of a custom implementation of the role service.
	RootBuilder	Infrastructure. Supports the page parser in defining the behavior for how content is parsed.
	ScriptBehaviorDescriptor	Extends the ScriptComponentDescriptor class to provide a wrapper for defining behaviors that are converted into client script.
	ScriptComponentDescriptor	Provides a wrapper for converting server components into client script.
	ScriptControl	Provides an abstract base class for a script control.
	ScriptControlDescriptor	Defines a client control object.
	ScriptDescriptor	When overridden in a derived class, defines script that creates an instance of a client class.
	ScriptManager	Manages ASP.NET AJAX script libraries and script files, partial-page rendering, and client proxy class generation for Web and application services.
	ScriptManagerProxy	Enables nested components such as content pages and user controls to add script and service references to pages when a ScriptManager control is already defined in a parent element.
	ScriptReference	Registers an ECMAScript (JavaScript) file for use on an ASP.NET Web page.
	ScriptReferenceBase	The base class for all script reference classes.
	ScriptReferenceCollection	Represents a collection of script references.
	ScriptReferenceEventArgs	Provides data for the ResolveScriptReference event.
	ScriptResourceAttribute	Defines a resource in an assembly to be used from a client script file. This class cannot be inherited.
	ServiceReference	Registers a Web service for use in a Web page.
	ServiceReferenceCollection	Contains a set of ServiceReference objects.
	SessionPageStatePersister	Stores ASP.NET page view state on the Web server.
	SimplePropertyEntry	Infrastructure. Represents the definition of the control property and its value.
	SimpleWebHandlerParser	Infrastructure. Provides base functionality for parsing Web handler files.
	SkinBuilder	Provides a ControlBuilder object used at design time to apply control skins to controls.
	StateBag	Manages the view state of ASP.NET server controls, including pages. This class cannot be inherited.
	StateItem	Represents an item that is saved in the StateBag class when view state information is persisted between Web requests. This class cannot be inherited.
	StateManagedCollection	Provides a base class for all strongly typed collections that manage IStateManager objects.
	StaticPartialCachingControl	Represents an instance of the UserControl class that is specified for output caching and included declaratively in a page or another user control.
	SupportsEventValidationAttribute	Defines the metadata attribute that Web server controls use to indicate support for event validation. This class cannot be inherited.
	TagPrefixAttribute	Defines the tag prefix used in a Web page to identify custom controls. This class cannot be inherited.
	TargetControlTypeAttribute	Extends the Attribute class to indicate the type of server control that an extender control can be applied to.
	TemplateBuilder	Supports the page parser in building a template and the child controls it contains.
	TemplateContainerAttribute	Declares the base type of the container control of a property that returns an ITemplate interface and is marked with the TemplateContainerAttribute attribute. The control with the ITemplate property must implement the INamingContainer interface. This class cannot be inherited.
	TemplateControl	Provides the Page class and the UserControl class with a base set of functionality.
	TemplateControlParser	Infrastructure. Implements ASP.NET template parsing for template controls.
	TemplateInstanceAttribute	Defines a metadata attribute that is used to specify the number of allowed instances of a template. This class cannot be inherited.
	TemplateParser	Infrastructure. Serves as the abstract base class for ASP.NET file parsers.
	TemplatePropertyEntry	Enables property entry for ITemplate class properties.
	ThemeableAttribute	Defines the metadata attribute that Web server controls and their members use to indicate whether their rendering can be affected by themes and control skins. This class cannot be inherited.
	ThemeProvider	Provides a class that encapsulates theme and style sheet information for controls in a designer environment.
	Timer	Performs asynchronous or synchronous Web page postbacks at a defined interval.
	ToolboxDataAttribute	Specifies the default tag generated for a custom control when it is dragged from a toolbox in a tool such as Microsoft Visual Studio.
	Triplet	Provides a basic utility class that is used to store three related objects.
	UpdatePanel	Enables sections of a page to be partially rendered without a postback.
	UpdatePanelControlTrigger	Provides a common base class for controls that can be triggers for UpdatePanel controls.
	UpdatePanelTrigger	Provides a common base class for objects that can be triggers for UpdatePanel controls.
	UpdatePanelTriggerCollection	Represents a collection of UpdatePanelTrigger objects for an UpdatePanel control.
	UpdateProgress	Provides visual feedback in the browser when the contents of one or more UpdatePanel controls are updated.
	UrlPropertyAttribute	Defines the attribute that controls use to identify string properties containing URL values. This class cannot be inherited.
	UserControl	Represents an .ascx file, also known as a user control, requested from a server that hosts an ASP.NET Web application. The file must be called from a Web Forms page or a parser error will occur.
	UserControlControlBuilder	Supports the ASP.NET page parser in building an instance of a user control.
	ValidationPropertyAttribute	Defines the metadata attribute that ASP.NET server controls use to identify a validation property. This class cannot be inherited.
	ValidatorCollection	Exposes an array of IValidator references. This class cannot be inherited.
	VerificationAttribute	Defines the metadata attribute of a Web content accessibility rule. This class cannot be inherited.
	ViewStateException	Represents the exception that is thrown when the view state cannot be loaded or validated. This class cannot be inherited.
	ViewStateModeByIdAttribute	Defines the metadata attribute that ASP.NET server controls use to specify whether they participate in loading view-state information by ID. This class cannot be inherited.
	WebResourceAttribute	Defines the metadata attribute that enables an embedded resource in an assembly. This class cannot be inherited.
	WebServiceParser	Infrastructure. Provides a parser for Web service handlers.
	XhtmlTextWriter	Writes Extensible Hypertext Markup Language (XHTML)-specific characters, including all variations of XHTML modules that derive from XTHML, to the output stream for an ASP.NET server control for mobile devices. Override the XhtmlTextWriter class to provide custom XHTML rendering for ASP.NET pages and server controls.
	XPathBinder	Provides support for rapid application development (RAD) designers to parse data-binding expressions that use XPath expressions. This class cannot be inherited.

Interfaces

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	Interface	Description
	IAttributeAccessor	Defines methods used by ASP.NET server controls to provide programmatic access to any attribute declared in the opening tag of a server control.
	IAutoFieldGenerator	Defines a method that automatically generates fields for data-bound controls that use ASP.NET Dynamic Data features.
	IBindableControl	Defines a method that enables field template controls to implement two-way data-binding.
	IBindableTemplate	Provides a way for ASP.NET data-bound controls, such as DetailsView and FormView, to automatically bind to an ASP.NET data source control within templated content sections.
	ICallbackEventHandler	Used to indicate that a control can be the target of a callback event on the server.
	ICheckBoxControl	Defines the property and event a control implements to act as a check box.
	IControlBuilderAccessor	Allows the control serializer to get to the builder for a control.
	IControlDesignerAccessor	Provides access to a control designer to store temporary design-time data associated with a control.
	IDataBindingsAccessor	Allows access to the collection of data-binding expressions on a control at design time.
	IDataItemContainer	Enables data-bound control containers to identify a data item object for simplified data-binding operations.
	IDataSource	Represents an abstract data source that data-bound controls bind to.
	IDataSourceViewSchemaAccessor	Allows a type converter to access schema information stored on an object.
	IEditableTextControl	Represents a control that renders text that can be changed by the user.
	IExpressionsAccessor	Infrastructure. Defines the properties a class must implement to support collections of expressions.
	IExtenderControl	Defines the behavior for an extender control.
	IFilterResolutionService	Provides an interface that designer developers can use to evaluate device filters by name.
	IHierarchicalDataSource	Represents a hierarchical data source that hierarchical data-bound controls such as TreeView can bind to.
	IHierarchicalEnumerable	Represents a hierarchical collection that can be enumerated with an IEnumerator interface. Collections that implement the IHierarchicalEnumerable interface are used by ASP.NET site navigation and data source controls.
	IHierarchyData	Exposes a node of a hierarchical data structure, including the node object and some properties that describe characteristics of the node. Objects that implement the IHierarchyData interface can be contained in IHierarchicalEnumerable collections, and are used by ASP.NET site navigation and data source controls.
	INamingContainer	Identifies a container control that creates a new ID namespace within a Page object's control hierarchy. This is a marker interface only.
	INavigateUIData	Provides an interface that classes implement to provide navigation user interface data and values to navigation controls.
	IParserAccessor	Defines the method that ASP.NET server controls must implement to recognize when elements, either HTML or XML, are parsed.
	IPostBackDataHandler	Defines methods that ASP.NET server controls must implement to automatically load postback data.
	IPostBackEventHandler	Defines the method ASP.NET server controls must implement to handle postback events.
	IResourceUrlGenerator	Defines the method that a designer-host must implement to provide URL reference look-up for embedded resources.
	IScriptControl	Defines methods that ASP.NET server controls must implement to define ECMAScript (JavaScript) resources in AJAX-enabled applications.
	IStateFormatter	Defines methods that a type implements to serialize and deserialize an object graph.
	IStateManager	Defines the properties and methods any class must implement to support view state management for a server control.
	IStyleSheet	Defines the methods that a class must implement in order to support the creation of style rules.
	ITemplate	Defines the behavior for populating a templated ASP.NET server control with child controls. The child controls represent the inline templates defined on the page.
	ITextControl	Defines the interface a control implements to get or set its text content.
	IThemeResolutionService	Provides an interface that designer tool developers can use to supply a set of ThemeProvider objects, which can be used to apply themes and control skins to controls in a design-time environment.
	IUrlResolutionService	Defines a service implemented by objects to resolve relative URLs based on contextual information.
	IUserControlDesignerAccessor	Defines the properties that allow the designer to access information about a user control at design time.
	IUserControlTypeResolutionService	Defines the method a class must implement to return a control's type for a specified tag prefix and tag name.
	IValidator	Defines the properties and methods that objects that participate in Web Forms validation must implement.

Delegates

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	Delegate	Description
	BuildMethod	Infrastructure. Represents the method that is used to build a control.
	BuildTemplateMethod	Infrastructure. Supports ASP.NET during the creation of a template for a templated control from generated class code. The BuildTemplateMethod delegate handles the InstantiateIn method.
	ControlSkinDelegate	Represents the method that applies the correct control skin to the specified control.
	DataSourceViewOperationCallback	Represents the asynchronous callback method that a data-bound control supplies to a data source view for asynchronous insert, update, or delete data operations.
	DataSourceViewSelectCallback	Represents the asynchronous callback method that a data-bound control supplies to a data source view for asynchronous data retrieval.
	ExtractTemplateValuesMethod	Infrastructure. Provides a delegate with which ASP.NET extracts a set of name/value pairs from an IBindableTemplate object at run time. This class cannot be inherited.
	ImageClickEventHandler	Represents the method that handles any events that are raised when a user clicks an image-based ASP.NET server control.
	RenderMethod	Infrastructure. Represents the method that renders the specified Control container to the specified HtmlTextWriter.

Enumerations

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	Enumeration	Description
	CodeConstructType	Specifies the code constructs that can be parsed in the ProcessCodeConstruct method of the PageParserFilter class.
	CompilationMode	Defines constants that specify how ASP.NET should compile .aspx pages and .ascx controls.
	ConflictOptions	Determines how ASP.NET data source controls handle data conflicts when updating or deleting data.
	DataSourceCacheExpiry	Describes the way data cached using ASP.NET caching mechanisms expires when a time-out is set.
	DataSourceCapabilities	Provides a way to request processing beyond record retrieval for a data retrieval operation of a data source control.
	DataSourceOperation	Specifies a data operation performed by a data source control.
	HtmlTextWriterAttribute	Specifies the HTML attributes that an HtmlTextWriter or Html32TextWriter object writes to the opening tag of an HTML element when a Web request is processed.
	HtmlTextWriterStyle	Specifies the HTML styles available to an HtmlTextWriter or Html32TextWriter object output stream.
	HtmlTextWriterTag	Specifies the HTML tags that can be passed to an HtmlTextWriter or Html32TextWriter object output stream.
	OutputCacheLocation	Specifies the valid values for controlling the location of the output-cached HTTP response for a resource.
	PersistenceMode	Specifies how an ASP.NET server control property or event is persisted declaratively in an .aspx or .ascx file.
	RegisteredScriptType	Specifies the type of client script block that is represented by a RegisteredScript object.
	ScriptMode	Specifies whether ScriptManager and ScriptReference objects refer to the debug or release version of client scripts.
	TemplateInstance	Specifies how many times an instance of a template can be created.
	UpdatePanelRenderMode	Represents the possible layout rendering options for the content of an UpdatePanel control on a page.
	UpdatePanelUpdateMode	Represents the possible update modes for the content in an UpdatePanel control.
	VerificationConditionalOperator	Specifies operators for a conditional expression used in a VerificationAttribute class.
	VerificationReportLevel	Specifies reporting levels for an accessibility rule defined by an VerificationAttribute instance.
	VerificationRule	Specifies how conditional expressions defined by an VerificationAttribute instance are used in verification.
	ViewStateEncryptionMode	Specifies whether view-state information is encrypted.
	VirtualReferenceType	Specifies the type of resource referenced by a parsed virtual path.
	XhtmlMobileDocType	Specifies the type of XHTML for the XhtmlTextWriter class to render to the page or control.