WebControl Class
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Serves as the base class that defines the methods, properties and events common to all controls in the System.Web.UI.WebControls namespace.
public ref class WebControl : System::Web::UI::Control, System::Web::UI::IAttributeAccessorpublic class WebControl : System.Web.UI.Control, System.Web.UI.IAttributeAccessor[System.Web.UI.Themeable(true)]
public class WebControl : System.Web.UI.Control, System.Web.UI.IAttributeAccessortype WebControl = class
inherit Control
interface IAttributeAccessor[<System.Web.UI.Themeable(true)>]
type WebControl = class
inherit Control
interface IAttributeAccessorPublic Class WebControl
Inherits Control
Implements IAttributeAccessor- Inheritance
- Derived
- Attributes
- Implements
Examples
namespace ControlTest
{
using System;
using System.Web.UI;
using System.Web.UI.WebControls;
// Renders the following HTML:
// <span onclick="alert('Hello');" style="color:Red;">Custom Contents</span>
public class MyWebControl: WebControl {
public MyWebControl() : base(HtmlTextWriterTag.Span)
{ }
[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
protected override void AddAttributesToRender(HtmlTextWriter writer)
{
writer.AddAttribute(HtmlTextWriterAttribute.Onclick, "alert('Hello');");
writer.AddStyleAttribute(HtmlTextWriterStyle.Color, "Red");
base.AddAttributesToRender(writer);
}
[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")]
protected override void RenderContents(HtmlTextWriter writer)
{
writer.Write("Custom Contents");
base.RenderContents(writer);
}
}
}
Imports System.Web.UI
Imports System.Web.UI.WebControls
Namespace ControlTest
' Renders the following HTML:
' <span onclick="alert('Hello');" style="color:Red;">Custom Contents</span>
Public Class MyWebControl
Inherits WebControl
Public Sub New()
MyBase.New(HtmlTextWriterTag.Span)
End Sub
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
Protected Overrides Sub AddAttributesToRender(writer As HtmlTextWriter)
writer.AddAttribute(HtmlTextWriterAttribute.Onclick, "alert('Hello');")
writer.AddStyleAttribute(HtmlTextWriterStyle.Color, "Red")
MyBase.AddAttributesToRender(writer)
End Sub
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
Protected Overrides Sub RenderContents(writer As HtmlTextWriter)
writer.Write("Custom Contents")
MyBase.RenderContents(writer)
End Sub
End Class
End Namespace 'ControlTest
Remarks
The WebControl class provides the properties, methods, and events that are common to all Web server controls. You can control the appearance and behavior of a Web server control by setting properties defined in this class. For example, the background color and font color of a control are controlled by using the BackColor and ForeColor properties, respectively. On controls that can display a border, you can control the border width, the border style, and the border color by setting the BorderWidth, BorderStyle, and BorderColor properties. The size of a Web server control can be specified by using the Height and Width properties.
The behavior of the control can be specified by setting certain properties. You can enable and disable a control by setting the Enabled property. The place of the control in the tab order is controlled by setting the TabIndex property. You can specify a ToolTip for the control by setting the ToolTip property.
Note
Not all controls support every property defined in this class. For specific information about whether a property is supported, see the documentation for the specific control.
Note
Some properties in this class render differently, depending on the browser. Some properties do not render at all, while others render, but have no effect. The TagWriter property of the HttpBrowserCapabilities object determines the way in which a Web server control renders. For browsers that support HTML 4.0, the TagWriter property will contain a regular HttpBrowserCapabilities object, and most properties will be rendered using HTML 4.0 style attributes. Browsers that are not known to support HTML 4.0 will use the Html32TextWriter object. This will automatically map the style attributes to any relevant HTML 3.2 tag attributes. In some cases, such as with the ForeColor property, the style attributes will be converted into additional tags, such as <font> tags. In some cases, there will be no mapping performed. For specific information about how a property is rendered in different browsers, see the documentation for the specific property.
For a list of initial property values for an instance of WebControl, see the WebControl constructor.
Constructors
| WebControl() |
Initializes a new instance of the WebControl class that represents a |
| WebControl(HtmlTextWriterTag) |
Initializes a new instance of the WebControl class using the specified HTML tag. |
| WebControl(String) |
Initializes a new instance of the WebControl class using the specified HTML tag. |
Properties
| AccessKey |
Gets or sets the access key that allows you to quickly navigate to the Web server control. |
| Adapter |
Gets the browser-specific adapter for the control. (Inherited from Control) |
| AppRelativeTemplateSourceDirectory |
Gets or sets the application-relative virtual directory of the Page or UserControl object that contains this control. (Inherited from Control) |
| Attributes |
Gets the collection of arbitrary attributes (for rendering only) that do not correspond to properties on the control. |
| BackColor |
Gets or sets the background color of the Web server control. |
| BindingContainer |
Gets the control that contains this control's data binding. (Inherited from Control) |
| BorderColor |
Gets or sets the border color of the Web control. |
| BorderStyle |
Gets or sets the border style of the Web server control. |
| BorderWidth |
Gets or sets the border width of the Web server control. |
| ChildControlsCreated |
Gets a value that indicates whether the server control's child controls have been created. (Inherited from Control) |
| ClientID |
Gets the control ID for HTML markup that is generated by ASP.NET. (Inherited from Control) |
| ClientIDMode |
Gets or sets the algorithm that is used to generate the value of the ClientID property. (Inherited from Control) |
| ClientIDSeparator |
Gets a character value representing the separator character used in the ClientID property. (Inherited from Control) |
| Context |
Gets the HttpContext object associated with the server control for the current Web request. (Inherited from Control) |
| Controls |
Gets a ControlCollection object that represents the child controls for a specified server control in the UI hierarchy. (Inherited from Control) |
| ControlStyle |
Gets the style of the Web server control. This property is used primarily by control developers. |
| ControlStyleCreated |
Gets a value indicating whether a Style object has been created for the ControlStyle property. This property is primarily used by control developers. |
| CssClass |
Gets or sets the Cascading Style Sheet (CSS) class rendered by the Web server control on the client. |
| DataItemContainer |
Gets a reference to the naming container if the naming container implements IDataItemContainer. (Inherited from Control) |
| DataKeysContainer |
Gets a reference to the naming container if the naming container implements IDataKeysControl. (Inherited from Control) |
| DesignMode |
Gets a value indicating whether a control is being used on a design surface. (Inherited from Control) |
| DisabledCssClass |
Gets or sets the CSS class to apply to the rendered HTML element when the control is disabled. |
| Enabled |
Gets or sets a value indicating whether the Web server control is enabled. |
| EnableTheming |
Gets or sets a value indicating whether themes apply to this control. |
| EnableTheming |
Gets or sets a value indicating whether themes apply to this control. (Inherited from Control) |
| 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. (Inherited from Control) |
| Events |
Gets a list of event handler delegates for the control. This property is read-only. (Inherited from Control) |
| Font |
Gets the font properties associated with the Web server control. |
| ForeColor |
Gets or sets the foreground color (typically the color of the text) of the Web server control. |
| HasAttributes |
Gets a value indicating whether the control has attributes set. |
| HasChildViewState |
Gets a value indicating whether the current server control's child controls have any saved view-state settings. (Inherited from Control) |
| Height |
Gets or sets the height of the Web server control. |
| ID |
Gets or sets the programmatic identifier assigned to the server control. (Inherited from Control) |
| IdSeparator |
Gets the character used to separate control identifiers. (Inherited from Control) |
| IsChildControlStateCleared |
Gets a value indicating whether controls contained within this control have control state. (Inherited from Control) |
| IsEnabled |
Gets a value indicating whether the control is enabled. |
| IsTrackingViewState |
Gets a value that indicates whether the server control is saving changes to its view state. (Inherited from Control) |
| IsViewStateEnabled |
Gets a value indicating whether view state is enabled for this control. (Inherited from Control) |
| LoadViewStateByID |
Gets a value indicating whether the control participates in loading its view state by ID instead of index. (Inherited from Control) |
| NamingContainer |
Gets a reference to the server control's naming container, which creates a unique namespace for differentiating between server controls with the same ID property value. (Inherited from Control) |
| Page |
Gets a reference to the Page instance that contains the server control. (Inherited from Control) |
| Parent |
Gets a reference to the server control's parent control in the page control hierarchy. (Inherited from Control) |
| RenderingCompatibility |
Gets a value that specifies the ASP.NET version that rendered HTML will be compatible with. (Inherited from Control) |
| Site |
Gets information about the container that hosts the current control when rendered on a design surface. (Inherited from Control) |
| SkinID |
Gets or sets the skin to apply to the control. |
| SkinID |
Gets or sets the skin to apply to the control. (Inherited from Control) |
| Style |
Gets a collection of text attributes that will be rendered as a style attribute on the outer tag of the Web server control. |
| SupportsDisabledAttribute |
Gets a value that indicates whether the control should set the |
| TabIndex |
Gets or sets the tab index of the Web server control. |
| TagKey |
Gets the HtmlTextWriterTag value that corresponds to this Web server control. This property is used primarily by control developers. |
| TagName |
Gets the name of the control tag. This property is used primarily by control developers. |
| TemplateControl |
Gets or sets a reference to the template that contains this control. (Inherited from Control) |
| TemplateSourceDirectory |
Gets the virtual directory of the Page or UserControl that contains the current server control. (Inherited from Control) |
| ToolTip |
Gets or sets the text displayed when the mouse pointer hovers over the Web server control. |
| UniqueID |
Gets the unique, hierarchically qualified identifier for the server control. (Inherited from Control) |
| ValidateRequestMode |
Gets or sets a value that indicates whether the control checks client input from the browser for potentially dangerous values. (Inherited from Control) |
| 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. (Inherited from Control) |
| ViewStateIgnoresCase |
Gets a value that indicates whether the StateBag object is case-insensitive. (Inherited from Control) |
| ViewStateMode |
Gets or sets the view-state mode of this control. (Inherited from Control) |
| Visible |
Gets or sets a value that indicates whether a server control is rendered as UI on the page. (Inherited from Control) |
| Width |
Gets or sets the width of the Web server control. |
Methods
| AddAttributesToRender(HtmlTextWriter) |
Adds HTML attributes and styles that need to be rendered to the specified HtmlTextWriterTag. This method is used primarily by control developers. |
| AddedControl(Control, Int32) |
Called after a child control is added to the Controls collection of the Control object. (Inherited from Control) |
| AddParsedSubObject(Object) |
Notifies the server control that an element, either XML or HTML, was parsed, and adds the element to the server control's ControlCollection object. (Inherited from Control) |
| ApplyStyle(Style) |
Copies any nonblank elements of the specified style to the Web control, overwriting any existing style elements of the control. This method is primarily used by control developers. |
| ApplyStyleSheetSkin(Page) |
Applies the style properties defined in the page style sheet to the control. (Inherited from Control) |
| BeginRenderTracing(TextWriter, Object) |
Begins design-time tracing of rendering data. (Inherited from Control) |
| BuildProfileTree(String, Boolean) |
Gathers information about the server control and delivers it to the Trace property to be displayed when tracing is enabled for the page. (Inherited from Control) |
| ClearCachedClientID() |
Sets the cached ClientID value to |
| ClearChildControlState() |
Deletes the control-state information for the server control's child controls. (Inherited from Control) |
| ClearChildState() |
Deletes the view-state and control-state information for all the server control's child controls. (Inherited from Control) |
| ClearChildViewState() |
Deletes the view-state information for all the server control's child controls. (Inherited from Control) |
| ClearEffectiveClientIDMode() |
Sets the ClientIDMode property of the current control instance and of any child controls to Inherit. (Inherited from Control) |
| CopyBaseAttributes(WebControl) |
Copies the properties not encapsulated by the Style object from the specified Web server control to the Web server control that this method is called from. This method is used primarily by control developers. |
| 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. (Inherited from Control) |
| CreateControlCollection() |
Creates a new ControlCollection object to hold the child controls (both literal and server) of the server control. (Inherited from Control) |
| CreateControlStyle() |
Creates the style object that is used internally by the WebControl class to implement all style related properties. This method is used primarily by control developers. |
| DataBind() |
Binds a data source to the invoked server control and all its child controls. (Inherited from Control) |
| DataBind(Boolean) |
Binds a data source to the invoked server control and all its child controls with an option to raise the DataBinding event. (Inherited from Control) |
| DataBindChildren() |
Binds a data source to the server control's child controls. (Inherited from Control) |
| Dispose() |
Enables a server control to perform final clean up before it is released from memory. (Inherited from Control) |
| EndRenderTracing(TextWriter, Object) |
Ends design-time tracing of rendering data. (Inherited from Control) |
| EnsureChildControls() |
Determines whether the server control contains child controls. If it does not, it creates child controls. (Inherited from Control) |
| EnsureID() |
Creates an identifier for controls that do not have an identifier assigned. (Inherited from Control) |
| Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
| FindControl(String, Int32) |
Searches the current naming container for a server control with the specified |
| FindControl(String) |
Searches the current naming container for a server control with the specified |
| Focus() |
Sets input focus to a control. (Inherited from Control) |
| GetDesignModeState() |
Gets design-time data for a control. (Inherited from Control) |
| GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
| GetRouteUrl(Object) |
Gets the URL that corresponds to a set of route parameters. (Inherited from Control) |
| GetRouteUrl(RouteValueDictionary) |
Gets the URL that corresponds to a set of route parameters. (Inherited from Control) |
| GetRouteUrl(String, Object) |
Gets the URL that corresponds to a set of route parameters and a route name. (Inherited from Control) |
| GetRouteUrl(String, RouteValueDictionary) |
Gets the URL that corresponds to a set of route parameters and a route name. (Inherited from Control) |
| GetType() |
Gets the Type of the current instance. (Inherited from Object) |
| GetUniqueIDRelativeTo(Control) |
Returns the prefixed portion of the UniqueID property of the specified control. (Inherited from Control) |
| HasControls() |
Determines if the server control contains any child controls. (Inherited from Control) |
| HasEvents() |
Returns a value indicating whether events are registered for the control or any child controls. (Inherited from Control) |
| IsLiteralContent() |
Determines if the server control holds only literal content. (Inherited from Control) |
| LoadControlState(Object) |
Restores control-state information from a previous page request that was saved by the SaveControlState() method. (Inherited from Control) |
| LoadViewState(Object) |
Restores view-state information from a previous request that was saved with the SaveViewState() method. |
| MapPathSecure(String) |
Retrieves the physical path that a virtual path, either absolute or relative, maps to. (Inherited from Control) |
| MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
| MergeStyle(Style) |
Copies any nonblank elements of the specified style to the Web control, but will not overwrite any existing style elements of the control. This method is used primarily by control developers. |
| OnBubbleEvent(Object, EventArgs) |
Determines whether the event for the server control is passed up the page's UI server control hierarchy. (Inherited from Control) |
| OnDataBinding(EventArgs) |
Raises the DataBinding event. (Inherited from Control) |
| OnInit(EventArgs) |
Raises the Init event. (Inherited from Control) |
| OnLoad(EventArgs) |
Raises the Load event. (Inherited from Control) |
| OnPreRender(EventArgs) |
Raises the PreRender event. (Inherited from Control) |
| OnUnload(EventArgs) |
Raises the Unload event. (Inherited from Control) |
| OpenFile(String) |
Gets a Stream used to read a file. (Inherited from Control) |
| RaiseBubbleEvent(Object, EventArgs) |
Assigns any sources of the event and its information to the control's parent. (Inherited from Control) |
| RemovedControl(Control) |
Called after a child control is removed from the Controls collection of the Control object. (Inherited from Control) |
| Render(HtmlTextWriter) |
Renders the control to the specified HTML writer. |
| RenderBeginTag(HtmlTextWriter) |
Renders the HTML opening tag of the control to the specified writer. This method is used primarily by control developers. |
| RenderChildren(HtmlTextWriter) |
Outputs the content of a server control's children to a provided HtmlTextWriter object, which writes the content to be rendered on the client. (Inherited from Control) |
| RenderContents(HtmlTextWriter) |
Renders the contents of the control to the specified writer. This method is used primarily by control developers. |
| RenderControl(HtmlTextWriter, ControlAdapter) |
Outputs server control content to a provided HtmlTextWriter object using a provided ControlAdapter object. (Inherited from Control) |
| RenderControl(HtmlTextWriter) |
Outputs server control content to a provided HtmlTextWriter object and stores tracing information about the control if tracing is enabled. (Inherited from Control) |
| RenderEndTag(HtmlTextWriter) |
Renders the HTML closing tag of the control into the specified writer. This method is used primarily by control developers. |
| ResolveAdapter() |
Gets the control adapter responsible for rendering the specified control. (Inherited from Control) |
| ResolveClientUrl(String) |
Gets a URL that can be used by the browser. (Inherited from Control) |
| ResolveUrl(String) |
Converts a URL into one that is usable on the requesting client. (Inherited from Control) |
| SaveControlState() |
Saves any server control state changes that have occurred since the time the page was posted back to the server. (Inherited from Control) |
| SaveViewState() |
Saves any state that was modified after the TrackViewState() method was invoked. |
| SetDesignModeState(IDictionary) |
Sets design-time data for a control. (Inherited from Control) |
| SetRenderMethodDelegate(RenderMethod) |
Assigns an event handler delegate to render the server control and its content into its parent control. (Inherited from Control) |
| 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. (Inherited from Control) |
| SetTraceData(Object, Object) |
Sets trace data for design-time tracing of rendering data, using the trace data key and the trace data value. (Inherited from Control) |
| ToString() |
Returns a string that represents the current object. (Inherited from Object) |
| TrackViewState() |
Causes the control to track changes to its view state so they can be stored in the object's ViewState property. |
Events
| DataBinding |
Occurs when the server control binds to a data source. (Inherited from Control) |
| 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. (Inherited from Control) |
| Init |
Occurs when the server control is initialized, which is the first step in its lifecycle. (Inherited from Control) |
| Load |
Occurs when the server control is loaded into the Page object. (Inherited from Control) |
| PreRender |
Occurs after the Control object is loaded but prior to rendering. (Inherited from Control) |
| Unload |
Occurs when the server control is unloaded from memory. (Inherited from Control) |
Explicit Interface Implementations
Extension Methods
| FindDataSourceControl(Control) |
Returns the data source that is associated with the data control for the specified control. |
| FindFieldTemplate(Control, String) |
Returns the field template for the specified column in the specified control's naming container. |
| FindMetaTable(Control) |
Returns the metatable object for the containing data control. |
