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Button.AddAttributesToRender(HtmlTextWriter) Method

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Adds the attributes of the Button control to the output stream for rendering on the client.

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 contains the output stream to render on the client.

Examples

The following code example demonstrates how to override the AddAttributesToRender method in a custom server control, so that the Button text always displays in red.

<%@ Page language="c#" %>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<!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 Button - AddAttributesToRender - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom Button - AddAttributesToRender - C# Example</h3>

      <aspSample:CustomButtonAddAttributesToRender
        id="Button1"
        runat="server"
        Text="Button" />

    </form>
  </body>
</html>

<%@ Page language="VB" %>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<!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 Button - AddAttributesToRender - VB.NET Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom Button - AddAttributesToRender - VB.NET Example</h3>
      <aspSample:CustomButtonAddAttributesToRender id="Button1" runat="server" Text="Button" />
    </form>
  </body>
</html>

using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
    [AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
    public sealed class CustomButtonAddAttributesToRender : System.Web.UI.WebControls.Button
    {
    protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer) 
    {
      // Add a client-side onclick event to the button.
      writer.AddAttribute(System.Web.UI.HtmlTextWriterAttribute.Onclick, "alert('Hello World');");

      // Update the text of the button to be shown in the color Red
      writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.Color, "Red");

      // Call the base's 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 CustomButtonAddAttributesToRender
        Inherits System.Web.UI.WebControls.Button

        Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)
            ' Add a client-side onclick event to the button.
            writer.AddAttribute(System.Web.UI.HtmlTextWriterAttribute.Onclick, "alert('Hello World');")

            ' Update the text of the button to be shown in the color Red
            writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.Color, "Red")

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

Applies to

See also