Sdílet prostřednictvím

Button.AddAttributesToRender(HtmlTextWriter) Metoda

  • Reference

Definice

Obor názvů:
System.Web.UI.WebControls
Sestavení:
System.Web.dll

Přidá atributy Button ovládacího prvku do výstupního datového proudu pro vykreslování na klientovi.

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)

Parametry

writer
HtmlTextWriter

Obsahuje HtmlTextWriter výstupní datový proud, který se má vykreslit na klientovi.

Příklady

Následující příklad kódu ukazuje, jak přepsat metodu AddAttributesToRender ve vlastním serverovém ovládacím prvku tak, aby se Button text vždy zobrazoval červeně.

<%@ 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

Platí pro

Viz také