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TextBox.AddAttributesToRender(HtmlTextWriter) Method

Definition

Adds HTML attributes and styles that need to be rendered to the specified HtmlTextWriter instance.

protected:
 override void AddAttributesToRender(System::Web::UI::HtmlTextWriter ^ writer);
protected override void AddAttributesToRender (System.Web.UI.HtmlTextWriter writer);
override this.AddAttributesToRender : System.Web.UI.HtmlTextWriter -> unit
Protected Overrides Sub AddAttributesToRender (writer As HtmlTextWriter)

Parameters

writer
HtmlTextWriter

An HtmlTextWriter that represents the output stream to render HTML content on the client.

Examples

The following code example demonstrates how to override the AddAttributesToRender method in a custom server control, so that the TextBox control text always appears bold.

Important

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.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
    <head>
        <title>Custom TextBox - AddAttributesToRender - C# Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom TextBox - AddAttributesToRender - C# Example</h3>
            
            <aspSample:CustomTextBoxAddAttributesToRender 
              id="TextBox1" 
              runat="server">Hello World!
            </aspSample:CustomTextBoxAddAttributesToRender>
            
        </form>
    </body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
    <head>
        <title>Custom TextBox - AddAttributesToRender - VB.NET Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom TextBox - AddAttributesToRender - VB.NET Example</h3>
            
            <aspSample:CustomTextBoxAddAttributesToRender id="TextBox1" 
             runat="server">Hello World!</aspSample:CustomTextBoxAddAttributesToRender>
        </form>
    </body>
</html>
using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomTextBoxAddAttributesToRender : System.Web.UI.WebControls.TextBox
  {
    protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer)
    {
      // Show the TextBox text as Bold.
      writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.FontWeight, "bold");

      // Call the base AddAttributesToRender method.
      base.AddAttributesToRender(writer);
    }
  }
}
Imports System.Web
Imports System.Security.Permissions

Namespace Samples.AspNet.VB.Controls
    <AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public NotInheritable Class CustomTextBoxAddAttributesToRender
        Inherits System.Web.UI.WebControls.TextBox

        Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)

            ' Show the TextBox text as Bold.
            writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.FontWeight, "bold")

            ' Call the base AddAttributesToRender method.
            MyBase.AddAttributesToRender(writer)
        End Sub
    End Class
End Namespace

Remarks

This method is used primarily by control developers to insert the additional attributes and styles to the HtmlTextWriter output stream for a TextBox control. This method overrides WebControl.AddAttributesToRender.

Applies to