WebControl.AddAttributesToRender Method
Assembly: System.Web (in system.web.dll)
'Declaration Protected Overridable Sub AddAttributesToRender ( _ writer As HtmlTextWriter _ ) 'Usage Dim writer As HtmlTextWriter Me.AddAttributesToRender(writer)
protected void AddAttributesToRender ( HtmlTextWriter writer )
protected function AddAttributesToRender ( writer : HtmlTextWriter )
Parameters
- writer
A HtmlTextWriter that represents the output stream to render HTML content on the client.
To render attributes and styles for a Web Server control on the client, you typically call the AddAttribute and System.Web.UI.HtmlTextWriter.AddStyleAttribute methods to insert each attribute and style individually to the HtmlTextWriter output stream. To simplify the process, this method encapsulates all calls to the System.Web.UI.HtmlTextWriter.AddAttribute and System.Web.UI.HtmlTextWriter.AddStyleAttribute methods for every attribute and style associated with the Web server control. All attributes and styles are inserted into the HtmlTextWriter output stream in a single method call. This method is typically overridden by control developers in derived classes to insert the appropriate attributes and styles to the HtmlTextWriter output stream for the class.
Note |
|---|
| The AddAttributesToRender method cannot be used to insert client script. To use client script, see the ClientScriptManager class. |
The following example demonstrates how to create a class that derives from the WebControl class. The base implementation of the AddAttributesToRender method is overridden to add attributes appropriate to the derived class in the HtmlTextWriter output stream.
Imports System 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 'New <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 'AddAttributesToRender <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 'RenderContents End Class 'MyWebControl End Namespace 'ControlTest
package ControlTest;
import System.*;
import System.Web.UI.*;
import System.Web.UI.WebControls.*;
// Renders the following HTML:
// <span onclick="alert('Hello');" style="color:Red;">Custom Contents</span>
public class MyWebControl extends WebControl
{
public MyWebControl()
{
super(HtmlTextWriterTag.Span);
} //MyWebControl
protected void AddAttributesToRender(HtmlTextWriter writer)
{
writer.AddAttribute(HtmlTextWriterAttribute.Onclick, "alert('Hello');");
writer.AddStyleAttribute(HtmlTextWriterStyle.Color, "Red");
super.AddAttributesToRender(writer);
} //AddAttributesToRender
/** @attribute System.Security.Permissions.PermissionSet(System.Security.
Permissions.SecurityAction.Demand, Name = "FullTrust")
*/
protected void RenderContents(HtmlTextWriter writer)
{
writer.Write("Custom Contents");
super.RenderContents(writer);
} //RenderContents
} //MyWebControl
Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.
Note