HtmlSelect.RenderAttributes(HtmlTextWriter) Metode
Definisi
Penting
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Merender HtmlSelect atribut kontrol ke objek yang ditentukan HtmlTextWriter .
protected:
override void RenderAttributes(System::Web::UI::HtmlTextWriter ^ writer);protected override void RenderAttributes(System.Web.UI.HtmlTextWriter writer);override this.RenderAttributes : System.Web.UI.HtmlTextWriter -> unitProtected Overrides Sub RenderAttributes (writer As HtmlTextWriter)Parameter
- writer
- HtmlTextWriter
HtmlTextWriter yang menerima konten yang dirender.
Contoh
Contoh kode berikut menunjukkan cara mengambil alih RenderAttributes metode dalam kontrol server kustom sehingga teks judul tertentu selalu ditampilkan untuk HtmlSelect kontrol.
<%@ 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 HtmlSelect - RenderAttributes - C# Example</title>
<script runat="server">
void HtmlInputButton1_ServerClick(Object sender, EventArgs e)
{
if (HtmlSelect1.SelectedIndex >= 0)
{
if (HtmlSelect1.Multiple)
{
Div1.InnerHtml = "You selected:";
for (int i=0; i<=HtmlSelect1.Items.Count - 1; i++)
{
if (HtmlSelect1.Items[i].Selected)
{
Div1.InnerHtml += "<br /> " + HtmlSelect1.Items[i].Value;
}
}
}
else
{
Div1.InnerHtml = "You selected " + HtmlSelect1.Value;
}
}
else
{
Div1.InnerHtml = "You did not select an item.";
}
}
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom HtmlSelect - RenderAttributes - C# Example</h3>
<p>
<aspSample:CustomHtmlSelectRenderAttributes
id="HtmlSelect1"
name="HtmlSelect1"
runat="server">
<option value="Option1">Option1</option>
<option value="Option2">Option2</option>
<option value="Option3">Option3</option>
</aspSample:CustomHtmlSelectRenderAttributes>
</p>
<p>
<input
id="HtmlInputButton1"
runat="server"
type="button"
onserverclick="HtmlInputButton1_ServerClick"
value="Select"
name="HtmlInputButton1" />
</p>
<br />
<div id="Div1" runat="server"
style="DISPLAY: inline; WIDTH: 256px; HEIGHT: 15px" />
</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 HtmlSelect - RenderAttributes - VB.NET Example</title>
<script runat="server">
Sub HtmlInputButton1_ServerClick(sender As Object, e As EventArgs)
If HtmlSelect1.SelectedIndex >= 0 Then
If HtmlSelect1.Multiple = True Then
Div1.InnerHtml = "You selected:"
Dim i As Integer
For i = 0 To HtmlSelect1.Items.Count - 1
If HtmlSelect1.Items(i).Selected = True Then
Div1.InnerHtml += "<br /> " & HtmlSelect1.Items(i).Value
End If
Next i
Else
Div1.InnerHtml = "You selected " & HtmlSelect1.Value
End If
Else
Div1.InnerHtml = "You did not select an item."
End If
End Sub
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom HtmlSelect - RenderAttributes - VB.NET Example</h3>
<p>
<aspSample:CustomHtmlSelectRenderAttributes
id="HtmlSelect1"
name="HtmlSelect1"
runat="server">
<option value="Option1">Option1</option>
<option value="Option2">Option2</option>
<option value="Option3">Option3</option>
</aspSample:CustomHtmlSelectRenderAttributes>
</p>
<p>
<input
id="HtmlInputButton1"
runat="server"
type="button"
onserverclick="HtmlInputButton1_ServerClick"
value="Select"
name="HtmlInputButton1" />
</p>
<br />
<div id="Div1" runat="server"
style="DISPLAY: inline; WIDTH: 256px; HEIGHT: 15px" />
</form>
</body>
</html>
using System.Web;
using System.Security.Permissions;
namespace Samples.AspNet.CS.Controls
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
public sealed class CustomHtmlSelectRenderAttributes : System.Web.UI.HtmlControls.HtmlSelect
{
protected override void RenderAttributes(System.Web.UI.HtmlTextWriter writer)
{
// Write out Title tag
writer.Write(" Title=\"Text from RenderAttributes.\"");
// Call the base's RenderAttributes method.
base.RenderAttributes(writer);
}
}
}
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomHtmlSelectRenderAttributes
Inherits System.Web.UI.HtmlControls.HtmlSelect
Protected Overrides Sub RenderAttributes(ByVal writer As System.Web.UI.HtmlTextWriter)
' Write out Title tag
writer.Write(" Title=""Text from RenderAttributes.""")
' Call the base's RenderAttributes method.
MyBase.RenderAttributes(writer)
End Sub
End Class
Keterangan
Metode ini RenderAttributes merender name atribut HtmlSelect kontrol secara langsung untuk memastikan bahwa ia memiliki nilai yang sama dengan Control.UniqueID properti . Setelah merender atribut, RenderAttributes metode memanggil metode kelas RenderAttributes dasar.
Metode RenderAttributes ini digunakan terutama oleh pengembang kontrol yang memperluas fungsionalitas HtmlSelect kontrol.
