Duration (Pacific Standard Time):
To (Pacific Standard Time):
Impact:
User Action:
.NET Framework Class Library

Control Class

Defines the properties, methods, and events that are shared by all ASP.NET server controls.

System.Object
  System.Web.UI.Control
    More...

Namespace:  System.Web.UI
Assembly:  System.Web (in System.Web.dll)
<BindableAttribute(True)> _
<ThemeableAttribute(False)> _
Public Class Control _
	Implements IComponent, IDisposable, IParserAccessor, IUrlResolutionService,  _
	IDataBindingsAccessor, IControlBuilderAccessor, IControlDesignerAccessor, IExpressionsAccessor

The Control type exposes the following members.

  Name Description
Public method Control Initializes a new instance of the Control class.
Top
  Name Description
Protected property Adapter Gets the browser-specific adapter for the control.
Public property AppRelativeTemplateSourceDirectory Gets or sets the application-relative virtual directory of the Page or UserControl object that contains this control.
Public property BindingContainer Infrastructure. Gets the control that contains this control's data binding.
Protected property ChildControlsCreated Gets a value that indicates whether the server control's child controls have been created.
Public property ClientID Gets the control ID for HTML markup that is generated by ASP.NET.
Public property ClientIDMode Gets or sets the algorithm that is used to generate the value of the ClientID property.
Protected property ClientIDSeparator Gets a character value representing the separator character used in the ClientID property.
Protected property Context Gets the HttpContext object associated with the server control for the current Web request.
Public property Controls Gets a ControlCollection object that represents the child controls for a specified server control in the UI hierarchy.
Public property DataItemContainer Gets a reference to the naming container if the naming container implements IDataItemContainer.
Public property DataKeysContainer Gets a reference to the naming container if the naming container implements IDataKeysControl.
Protected property DesignMode Gets a value indicating whether a control is being used on a design surface.
Public property EnableTheming Gets or sets a value indicating whether themes apply to this control.
Public property EnableViewState Gets or sets a value indicating whether the server control persists its view state, and the view state of any child controls it contains, to the requesting client.
Protected property Events Gets a list of event handler delegates for the control. This property is read-only.
Protected property HasChildViewState Gets a value indicating whether the current server control's child controls have any saved view-state settings.
Public property ID Gets or sets the programmatic identifier assigned to the server control.
Protected property IdSeparator Infrastructure. Gets the character used to separate control identifiers.
Protected property IsChildControlStateCleared Gets a value indicating whether controls contained within this control have control state.
Protected property IsTrackingViewState Gets a value that indicates whether the server control is saving changes to its view state.
Protected property IsViewStateEnabled Gets a value indicating whether view state is enabled for this control.
Protected property LoadViewStateByID Gets a value indicating whether the control participates in loading its view state by ID instead of index.
Public property NamingContainer Gets a reference to the server control's naming container, which creates a unique namespace for differentiating between server controls with the same Control.ID property value.
Public property Page Gets a reference to the Page instance that contains the server control.
Public property Parent Gets a reference to the server control's parent control in the page control hierarchy.
Public property RenderingCompatibility Gets a value that specifies the ASP.NET version that rendered HTML will be compatible with.
Public property Site Gets information about the container that hosts the current control when rendered on a design surface.
Public property SkinID Gets or sets the skin to apply to the control.
Public property TemplateControl Gets or sets a reference to the template that contains this control.
Public property TemplateSourceDirectory Gets the virtual directory of the Page or UserControl that contains the current server control.
Public property UniqueID Gets the unique, hierarchically qualified identifier for the server control.
Public property ValidateRequestMode Gets or sets a value that indicates whether the control checks client input from the browser for potentially dangerous values.
Protected property ViewState Gets a dictionary of state information that allows you to save and restore the view state of a server control across multiple requests for the same page.
Protected property ViewStateIgnoresCase Gets a value that indicates whether the StateBag object is case-insensitive.
Public property ViewStateMode Gets or sets the view-state mode of this control.
Public property Visible Gets or sets a value that indicates whether a server control is rendered as UI on the page.
Top
  Name Description
Protected method AddedControl Called after a child control is added to the Controls collection of the Control object.
Protected method AddParsedSubObject Notifies the server control that an element, either XML or HTML, was parsed, and adds the element to the server control's ControlCollection object.
Public method ApplyStyleSheetSkin Applies the style properties defined in the page style sheet to the control.
Protected method BeginRenderTracing Begins design-time tracing of rendering data.
Protected method BuildProfileTree Infrastructure. Gathers information about the server control and delivers it to the Trace property to be displayed when tracing is enabled for the page.
Protected method ClearCachedClientID Infrastructure. Sets the cached ClientID value to null.
Protected method ClearChildControlState Deletes the control-state information for the server control's child controls.
Protected method ClearChildState Deletes the view-state and control-state information for all the server control's child controls.
Protected method ClearChildViewState Deletes the view-state information for all the server control's child controls.
Protected method ClearEffectiveClientIDMode Infrastructure. Sets the ClientIDMode property of the current control instance and of any child controls to Inherit.
Protected method CreateChildControls Called by the ASP.NET page framework to notify server controls that use composition-based implementation to create any child controls they contain in preparation for posting back or rendering.
Protected method CreateControlCollection Creates a new ControlCollection object to hold the child controls (both literal and server) of the server control.
Public method DataBind() Binds a data source to the invoked server control and all its child controls.
Protected method DataBind(Boolean) Binds a data source to the invoked server control and all its child controls with an option to raise the DataBinding event.
Protected method DataBindChildren Binds a data source to the server control's child controls.
Public method Dispose Enables a server control to perform final clean up before it is released from memory.
Protected method EndRenderTracing Ends design-time tracing of rendering data.
Protected method EnsureChildControls Determines whether the server control contains child controls. If it does not, it creates child controls.
Protected method EnsureID Creates an identifier for controls that do not have an identifier assigned.
Public method Equals(Object) Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method FindControl(String) Searches the current naming container for a server control with the specified id parameter.
Protected method FindControl(String, Int32) Infrastructure. Searches the current naming container for a server control with the specified id and an integer, specified in the pathOffset parameter, which aids in the search. You should not override this version of the FindControl method.
Public method Focus Sets input focus to a control.
Protected method GetDesignModeState Infrastructure. Gets design-time data for a control.
Public method GetHashCode Serves as the default hash function. (Inherited from Object.)
Public method GetRouteUrl(Object) Gets the URL that corresponds to a set of route parameters.
Public method GetRouteUrl(RouteValueDictionary) Gets the URL that corresponds to a set of route parameters.
Public method GetRouteUrl(String, Object) Gets the URL that corresponds to a set of route parameters and a route name.
Public method GetRouteUrl(String, RouteValueDictionary) Gets the URL that corresponds to a set of route parameters and a route name.
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method GetUniqueIDRelativeTo Returns the prefixed portion of the UniqueID property of the specified control.
Public method HasControls Determines if the server control contains any child controls.
Protected method HasEvents Returns a value indicating whether events are registered for the control or any child controls.
Protected method IsLiteralContent Infrastructure. Determines if the server control holds only literal content.
Protected method LoadControlState Restores control-state information from a previous page request that was saved by the SaveControlState method.
Protected method LoadViewState Restores view-state information from a previous page request that was saved by the SaveViewState method.
Protected method MapPathSecure Retrieves the physical path that a virtual path, either absolute or relative, maps to.
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Protected method OnBubbleEvent Determines whether the event for the server control is passed up the page's UI server control hierarchy.
Protected method OnDataBinding Raises the DataBinding event.
Protected method OnInit Raises the Init event.
Protected method OnLoad Raises the Load event.
Protected method OnPreRender Raises the PreRender event.
Protected method OnUnload Raises the Unload event.
Protected method OpenFile Gets a Stream used to read a file.
Protected method RaiseBubbleEvent Assigns any sources of the event and its information to the control's parent.
Protected method RemovedControl Called after a child control is removed from the Controls collection of the Control object.
Protected method Render Sends server control content to a provided HtmlTextWriter object, which writes the content to be rendered on the client.
Protected method RenderChildren Outputs the content of a server control's children to a provided HtmlTextWriter object, which writes the content to be rendered on the client.
Public method RenderControl(HtmlTextWriter) Outputs server control content to a provided HtmlTextWriter object and stores tracing information about the control if tracing is enabled.
Protected method RenderControl(HtmlTextWriter, ControlAdapter) Outputs server control content to a provided HtmlTextWriter object using a provided ControlAdapter object.
Protected method ResolveAdapter Gets the control adapter responsible for rendering the specified control.
Public method ResolveClientUrl Gets a URL that can be used by the browser.
Public method ResolveUrl Converts a URL into one that is usable on the requesting client.
Protected method SaveControlState Saves any server control state changes that have occurred since the time the page was posted back to the server.
Protected method SaveViewState Saves any server control view-state changes that have occurred since the time the page was posted back to the server.
Protected method SetDesignModeState Sets design-time data for a control.
Public method SetRenderMethodDelegate Infrastructure. Assigns an event handler delegate to render the server control and its content into its parent control.
Public method SetTraceData(Object, Object) Sets trace data for design-time tracing of rendering data, using the trace data key and the trace data value.
Public method SetTraceData(Object, Object, Object) Sets trace data for design-time tracing of rendering data, using the traced object, the trace data key, and the trace data value.
Public method ToString Returns a string that represents the current object. (Inherited from Object.)
Protected method TrackViewState Causes tracking of view-state changes to the server control so they can be stored in the server control's StateBag object. This object is accessible through the Control.ViewState property.
Top
  Name Description
Public event DataBinding Occurs when the server control binds to a data source.
Public event Disposed Occurs when a server control is released from memory, which is the last stage of the server control lifecycle when an ASP.NET page is requested.
Public event Init Occurs when the server control is initialized, which is the first step in its lifecycle.
Public event Load Occurs when the server control is loaded into the Page object.
Public event PreRender Occurs after the Control object is loaded but prior to rendering.
Public event Unload Occurs when the server control is unloaded from memory.
Top
  Name Description
Public Extension Method FindDataSourceControl Returns the data source that is associated with the data control for the specified control. (Defined by DynamicDataExtensions.)
Public Extension Method FindFieldTemplate Returns the field template for the specified column in the specified control's naming container. (Defined by DynamicDataExtensions.)
Public Extension Method FindMetaTable Returns the metatable object for the containing data control. (Defined by DynamicDataExtensions.)
Top

This is the primary class that you derive from when you develop custom ASP.NET server controls. Control does not have any user interface (UI) specific features. If you are authoring a control that does not have a UI, or combines other controls that render their own UI, derive from Control. If you are authoring a control that does have a UI, derive from WebControl or any control in the System.Web.UI.WebControls namespace that provides an appropriate starting point for your custom control.

The Control class is the base class for all ASP.NET server controls, including custom controls, user controls, and pages. ASP.NET pages are instances of the Page class, which inherits from the Control class, and that handle requests for files that have an .aspx extension.

The Control class can directly or indirectly be used as part of the user interface for your Web application, and as such should be scrutinized to make sure best practices for writing secure code and securing applications are followed.

For general information on these topics, see Overview of Web Application Security Threats, Security Policy Best Practices, and Key Security Concepts. For more specific information, see Securing Standard Controls, How to: Display Safe Error Messages, How to: Protect Against Script Exploits in a Web Application by Applying HTML Encoding to Strings, and Introduction to the Validation Controls.

Topic Location
Walkthrough: Developing and Using a Custom Server Control Authoring ASP.NET Controls
Developing Custom Data-Bound Web Server Controls for ASP.NET 1.1 Authoring ASP.NET Controls
Walkthrough: Creating a Custom Data-Bound ASP.NET Web Control for ASP.NET 2.0 Authoring ASP.NET Controls
Walkthrough: Creating a Custom Data-Bound ASP.NET Web Control for ASP.NET 1.1 Authoring ASP.NET Controls
How to: Locate the Web Forms Controls on a Page by Walking the Controls Collection Building ASP .NET Web Applications
Walkthrough: Creating a Custom Data-Bound ASP.NET Web Control for ASP.NET 1.1 Building ASP .NET Web Applications in Visual Studio
Developing Custom Data-Bound Web Server Controls for ASP.NET 1.1 Building ASP .NET Web Applications in Visual Studio
Developing Custom Data-Bound Web Server Controls for ASP.NET 2.0 Authoring ASP.NET Controls
Developing Custom Data-Bound Web Server Controls for ASP.NET 1.1 Authoring ASP.NET Controls
How to: Locate Child Controls by ID in an ASP.NET Web Page Building ASP .NET Web Applications
How to: Locate Child Controls by ID in an ASP.NET Web Page Building ASP .NET Web Applications
Developing Custom Data-Bound Web Server Controls for ASP.NET 2.0 Authoring ASP.NET Controls
Walkthrough: Creating a Custom Data-Bound ASP.NET Web Control for ASP.NET 1.1 Authoring ASP.NET Controls
Walkthrough: Creating a Custom Data-Bound ASP.NET Web Control for ASP.NET 2.0 Authoring ASP.NET Controls
How to: Locate the Web Forms Controls on a Page by Walking the Controls Collection Building ASP .NET Web Applications
Walkthrough: Developing and Using a Custom Server Control Authoring ASP.NET Controls

The following example demonstrates a custom server control that derives from the Control class. The InnerContent class overrides the Control.Render method, checks to see if the class has any child controls on the page and determines whether the first child of the control is a literal control. If both of these conditions are met, the overridden method writes the HTML string <H2>Your Message:, the contents of the literal control, and a closing </H2> tag to the Web Forms page.

Security note Security Note

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

Option Explicit
Option Strict

Imports System
Imports System.Web
Imports System.Web.UI
Imports Microsoft.VisualBasic

Namespace SimpleControlSamples
    Public Class InnerContent
        Inherits Control
        <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="Execution")> _
        Protected Overrides Sub Render(output As HtmlTextWriter)

            If HasControls() And TypeOf Controls(0) Is LiteralControl Then
                output.Write("<H2>Your message : ")
                Controls(0).RenderControl(output)
                output.Write("</H2>")
            End If 
        End Sub 'Render
    End Class 'InnerContent
End Namespace 'SimpleControlSamples

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
System.Object
  System.Web.UI.Control
    System.Web.DynamicData.DynamicControl
    System.Web.DynamicData.DynamicDataManager
    System.Web.DynamicData.DynamicEntity
    System.Web.DynamicData.DynamicFilter
    System.Web.DynamicData.EntityTemplate
    System.Web.DynamicData.QueryableFilterRepeater
    System.Web.UI.BasePartialCachingControl
    System.Web.UI.DataBoundLiteralControl
    System.Web.UI.DataSourceControl
    System.Web.UI.DesignerDataBoundLiteralControl
    System.Web.UI.ExtenderControl
    System.Web.UI.HierarchicalDataSourceControl
    System.Web.UI.HtmlControls.HtmlControl
    System.Web.UI.LiteralControl
    System.Web.UI.MobileControls.DeviceSpecific
    System.Web.UI.MobileControls.MobileControl
    System.Web.UI.ScriptManager
    System.Web.UI.ScriptManagerProxy
    System.Web.UI.TemplateControl
    System.Web.UI.Timer
    System.Web.UI.UpdatePanel
    System.Web.UI.UpdateProgress
    System.Web.UI.WebControls.Content
    System.Web.UI.WebControls.ContentPlaceHolder
    System.Web.UI.WebControls.DataPager
    System.Web.UI.WebControls.DataPagerFieldItem
    System.Web.UI.WebControls.HiddenField
    System.Web.UI.WebControls.ListViewItem
    System.Web.UI.WebControls.Literal
    System.Web.UI.WebControls.LoginView
    System.Web.UI.WebControls.MenuItemTemplateContainer
    System.Web.UI.WebControls.MultiView
    System.Web.UI.WebControls.PlaceHolder
    System.Web.UI.WebControls.QueryExtender
    System.Web.UI.WebControls.Repeater
    System.Web.UI.WebControls.RepeaterItem
    System.Web.UI.WebControls.Substitution
    System.Web.UI.WebControls.View
    System.Web.UI.WebControls.WebControl
    System.Web.UI.WebControls.WebParts.ProxyWebPartManager
    System.Web.UI.WebControls.WebParts.WebPartManager
    System.Web.UI.WebControls.Xml