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RadioButtonList.Render(HtmlTextWriter) Metoda

  • Odwołanie

Definicja

Przestrzeń nazw:
System.Web.UI.WebControls
Zestaw:
System.Web.dll

Wyświetla kontrolkę RadioButtonList na kliencie.

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

Parametry

writer
HtmlTextWriter

Element HtmlTextWriter zawierający strumień wyjściowy do renderowania na kliencie.

Przykłady

W poniższym przykładzie kodu pokazano, jak zastąpić metodę Render w niestandardowej kontrolce serwera, aby kontrolka RadioButtonList zawsze wyświetlała się z tekstem opisowym.

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ 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 RadioButtonList - Render - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom RadioButtonList - Render - C# Example</h3>

      <aspSample:CustomRadioButtonListRender 
        id="Radiobuttonlist1" 
        runat="server" 
        RepeatColumns="2" 
        RepeatDirection="Horizontal">
        <asp:ListItem Value="Item1">Item1</asp:ListItem>
        <asp:ListItem Value="Item2">Item2</asp:ListItem>
        <asp:ListItem Value="Item3">Item3</asp:ListItem>
        <asp:ListItem Value="Item4">Item4</asp:ListItem>
      </aspSample:CustomRadioButtonListRender>
      
    </form>
  </body>
</html>

<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ 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 RadioButtonList - Render - VB.NET Example</title>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom RadioButtonList - Render - VB.NET Example</h3>

            <aspSample:CustomRadioButtonListRender
             id="Radiobuttonlist1" runat="server" 
             RepeatColumns="2" RepeatDirection="Horizontal">
                <asp:ListItem Value="Item1">Item1</asp:ListItem>
                <asp:ListItem Value="Item2">Item2</asp:ListItem>
                <asp:ListItem Value="Item3">Item3</asp:ListItem>
                <asp:ListItem Value="Item4">Item4</asp:ListItem>
            </aspSample:CustomRadioButtonListRender>
        </form>
    </body>
</html>

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

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomRadioButtonListRender : System.Web.UI.WebControls.RadioButtonList
  {
    protected override void Render(System.Web.UI.HtmlTextWriter writer)
    {
      // Call the base RenderContents method.
      base.Render(writer);

      // Append some text to the Image.
      writer.Write("Experience Windows Server 2003 and Visual Studio® .NET 2003.");
    }
  }
}

Imports System.Web
Imports System.Security.Permissions

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

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

            ' Call the base RenderContents method.
            MyBase.Render(writer)

            ' Append some text to the Image.
            writer.Write("Experience Windows Server 2003 and Visual Studio .NET 2003.")
        End Sub
    End Class
End Namespace

Uwagi

Ta metoda jest używana głównie przez deweloperów kontrolek w kontrolkach niestandardowych, które pochodzą z RadioButtonList klasy .

Implementacja Render metody kontrolki inicjuje RepeatInfoRadioButtonList obiekt listy i wywołuje RenderRepeater metodę, która z kolei używa RenderItem metody do renderowania poszczególnych elementów listy przycisków radiowych.

Dotyczy

Zobacz też