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HtmlMeta Class

Definition

Allows programmatic access to the HTML <meta> tag on the server.

public ref class HtmlMeta : System::Web::UI::HtmlControls::HtmlControl
public class HtmlMeta : System.Web.UI.HtmlControls.HtmlControl
type HtmlMeta = class
    inherit HtmlControl
Public Class HtmlMeta
Inherits HtmlControl
Inheritance

Examples

The following code example demonstrates how to use the HtmlMeta control to define HTML <meta> elements for a Web page. Two <meta> elements are defined, one listing keywords describing the page and one listing the date the page was created.

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

  protected void Page_Load(object sender, EventArgs e)
  {
    // Create two instances of an HtmlMeta control.
    HtmlMeta hm1 = new HtmlMeta();
    HtmlMeta hm2 = new HtmlMeta();    

    // Get a reference to the page header element.
    HtmlHead head = (HtmlHead)Page.Header;
    
    // Define an HTML <meta> element that is useful for search engines.
    hm1.Name = "keywords";
    hm1.Content = "words that describe your web page";
    head.Controls.Add(hm1);
    
    // Define an HTML <meta> element with a Scheme attribute.
    hm2.Name = "date";
    hm2.Content = DateTime.Now.ToString("yyyy-MM-dd");
    hm2.Scheme = "YYYY-MM-DD";
    head.Controls.Add(hm2);
    
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>HtmlMeta Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    View the HTML source code of the page to see the two HTML meta elements added.
    </div>
    </form>
</body>
</html>
<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

  Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
    
    ' Create two instances of an HtmlMeta control.
    Dim hm1 As New HtmlMeta()
    Dim hm2 As New HtmlMeta()
    
    ' Get a reference to the page header element.
    Dim head As HtmlHead = Page.Header

    ' Define an HTML <meta> element that is useful for search engines.
    hm1.Name = "keywords"
    hm1.Content = "words that describe your web page"
    head.Controls.Add(hm1)

    ' Define an HTML <meta> element with a Scheme attribute.
    hm2.Name = "date"
    hm2.Content = DateTime.Now.ToString("yyyy-MM-dd")
    hm2.Scheme = "YYYY-MM-DD"
    head.Controls.Add(hm2)

  End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>HtmlMeta Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    View the HTML source code of the page to see the two HTML meta elements added.
    </div>
    </form>
</body>
</html>

Remarks

The HtmlMeta control provides programmatic access to the HTML <meta> element on the server. The HTML <meta> element is a container for data about the rendered page, but not page content itself. The <meta> tag is placed between the opening and closing HTML <head> elements. Each <meta> element describes a metadata property name and its associated value.

Use the HtmlMeta control's Name property to specify the metadata property name, and the Content property to specify the metadata property value. Use the Scheme property to specify additional information to user agents on how to interpret the metadata property. Use the HttpEquiv property in place of the Name property when the resulting metadata property will be retrieved using HTTP.

You can get a reference to the page <head> element using the Header property of the Page object.

Constructors

HtmlMeta()

Initializes a new instance of the HtmlMeta class.

Properties

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 a collection of all attribute name and value pairs expressed on a server control tag within the ASP.NET page.

(Inherited from HtmlControl)
BindingContainer

Gets the control that contains this control's data binding.

(Inherited from 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)
Content

Gets or sets the metadata property value defined by the HtmlMeta 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)
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)
Disabled

Gets or sets a value indicating whether the HTML server control is disabled.

(Inherited from HtmlControl)
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)
HasChildViewState

Gets a value indicating whether the current server control's child controls have any saved view-state settings.

(Inherited from Control)
HttpEquiv

Gets or sets an HtmlMeta control property that is included in the HTTP response header.

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)
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)
Name

Gets or sets the metadata property name defined by the HtmlMeta 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)
Scheme

Gets or sets a scheme attribute used to interpret the metadata property value defined by the HtmlMeta 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.

(Inherited from Control)
Style

Gets a collection of all cascading style sheet (CSS) properties applied to a specified HTML server control in the ASP.NET file.

(Inherited from HtmlControl)
TagName

Gets the element name of a tag that contains a runat=server attribute and value pair.

(Inherited from HtmlControl)
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)
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 HtmlControl view state is case-sensitive.

(Inherited from HtmlControl)
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)

Methods

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)
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 null.

(Inherited from Control)
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)
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 HtmlControl)
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 id and an integer, specified in the pathOffset parameter, which aids in the search. You should not override this version of the FindControl method.

(Inherited from Control)
FindControl(String)

Searches the current naming container for a server control with the specified id parameter.

(Inherited from Control)
Focus()

Sets input focus to a control.

(Inherited from Control)
GetAttribute(String)

Gets the value of the named attribute on the HtmlControl control.

(Inherited from HtmlControl)
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 page request that was saved by the SaveViewState() method.

(Inherited from Control)
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)
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 HtmlMeta control to the client's browser using the specified HtmlTextWriter object.

RenderAttributes(HtmlTextWriter)

Renders the HtmlControl control's attributes into the specified HtmlTextWriter object.

(Inherited from HtmlControl)
RenderBeginTag(HtmlTextWriter)

Renders the opening HTML tag of the control into the specified HtmlTextWriter object.

(Inherited from HtmlControl)
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)
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)
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 server control view-state changes that have occurred since the time the page was posted back to the server.

(Inherited from Control)
SetAttribute(String, String)

Sets the value of the named attribute on the HtmlControl control.

(Inherited from HtmlControl)
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 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 ViewState property.

(Inherited from Control)

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

IAttributeAccessor.GetAttribute(String)

For a description of this member, see GetAttribute(String).

(Inherited from HtmlControl)
IAttributeAccessor.SetAttribute(String, String)

For a description of this member, see SetAttribute(String, String).

(Inherited from HtmlControl)
IControlBuilderAccessor.ControlBuilder

For a description of this member, see ControlBuilder.

(Inherited from Control)
IControlDesignerAccessor.GetDesignModeState()

For a description of this member, see GetDesignModeState().

(Inherited from Control)
IControlDesignerAccessor.SetDesignModeState(IDictionary)

For a description of this member, see SetDesignModeState(IDictionary).

(Inherited from Control)
IControlDesignerAccessor.SetOwnerControl(Control)

For a description of this member, see SetOwnerControl(Control).

(Inherited from Control)
IControlDesignerAccessor.UserData

For a description of this member, see UserData.

(Inherited from Control)
IDataBindingsAccessor.DataBindings

For a description of this member, see DataBindings.

(Inherited from Control)
IDataBindingsAccessor.HasDataBindings

For a description of this member, see HasDataBindings.

(Inherited from Control)
IExpressionsAccessor.Expressions

For a description of this member, see Expressions.

(Inherited from Control)
IExpressionsAccessor.HasExpressions

For a description of this member, see HasExpressions.

(Inherited from Control)
IParserAccessor.AddParsedSubObject(Object)

For a description of this member, see AddParsedSubObject(Object).

(Inherited from Control)

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.

Applies to

See also