HtmlInputRadioButton.OnPreRender(EventArgs) Methode
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Hiermee wordt de PreRender gebeurtenis gegenereerd en wordt het HtmlInputRadioButton besturingselement geregistreerd als een besturingselement waarvoor het afhandelen van terugstortingen is vereist.
protected:
override void OnPreRender(EventArgs ^ e);
protected public:
override void OnPreRender(EventArgs ^ e);
protected override void OnPreRender(EventArgs e);
protected internal override void OnPreRender(EventArgs e);
override this.OnPreRender : EventArgs -> unit
Protected Overrides Sub OnPreRender (e As EventArgs)
Protected Friend Overrides Sub OnPreRender (e As EventArgs)
Parameters
Voorbeelden
In het volgende codevoorbeeld ziet u hoe u de OnPreRender methode overschrijft, zodat er een Title kenmerk wordt toegevoegd aan een aangepast serverbeheer HtmlInputRadioButton .
<%@ 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 HtmlInputRadioButton - OnPreRender - C# Example</title>
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
Div1.InnerHtml = "";
}
void HtmlInputRadioButtonGroup1_ServerChange(object sender, System.EventArgs e)
{
// Diplay the value of the selected HtmlInputRadioButton control.
System.Web.UI.HtmlControls.HtmlInputRadioButton htmlInputRadioButtonGroup1 = (System.Web.UI.HtmlControls.HtmlInputRadioButton) sender;
Div1.InnerHtml = "You change your selection to: " + htmlInputRadioButtonGroup1.Value;
}
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom HtmlInputRadioButton - OnPreRender - C# Example</h3>
<aspSample:CustomHtmlInputRadioButtonOnPreRender
id="HtmlInputRadioButton1"
name="HtmlInputRadioButtonGroup1"
runat="server"
type="radio" checked
onserverchange="HtmlInputRadioButtonGroup1_ServerChange"
value="HtmlInputRadioButton1">HtmlInputRadioButton1
</aspSample:CustomHtmlInputRadioButtonOnPreRender>
<br />
<aspSample:CustomHtmlInputRadioButtonOnPreRender
id="HtmlInputRadioButton2"
name="HtmlInputRadioButtonGroup1"
runat="server"
type="radio"
onserverchange="HtmlInputRadioButtonGroup1_ServerChange"
value="HtmlInputRadioButton2">HtmlInputRadioButton2
</aspSample:CustomHtmlInputRadioButtonOnPreRender>
<p>
<input type="submit" value="Submit" id="Submit1" name="Submit1" runat="server" />
</p>
<div
id="Div1"
runat="server"
style="DISPLAY: inline; WIDTH: 256px; HEIGHT: 15px" />
</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 HtmlInputRadioButton - OnPreRender - Visual Basic Example</title>
<script runat="server">
Sub Page_Load(sender As Object, e As EventArgs)
Div1.InnerHtml = ""
End Sub
Sub HtmlInputRadioButtonGroup1_ServerChange(sender As Object, e As System.EventArgs)
Dim htmlInputRadioButtonGroup1 As System.Web.UI.HtmlControls.HtmlInputRadioButton = CType(sender, System.Web.UI.HtmlControls.HtmlInputRadioButton)
Div1.InnerHtml = "You change your selection to: " & htmlInputRadioButtonGroup1.Value
End Sub
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom HtmlInputRadioButton - OnPreRender - Visual Basic Example</h3>
<aspSample:CustomHtmlInputRadioButtonOnPreRender
id="HtmlInputRadioButton1"
name="HtmlInputRadioButtonGroup1"
runat="server"
type="radio" checked
onserverchange="HtmlInputRadioButtonGroup1_ServerChange"
value="HtmlInputRadioButton1">HtmlInputRadioButton1
</aspSample:CustomHtmlInputRadioButtonOnPreRender>
<br />
<aspSample:CustomHtmlInputRadioButtonOnPreRender
id="HtmlInputRadioButton2"
name="HtmlInputRadioButtonGroup1"
runat="server"
type="radio"
onserverchange="HtmlInputRadioButtonGroup1_ServerChange"
value="HtmlInputRadioButton2">HtmlInputRadioButton2
</aspSample:CustomHtmlInputRadioButtonOnPreRender>
<p>
<input type="submit" value="Submit" id="Submit1" name="Submit1" runat="server" />
</p>
<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 CustomHtmlInputRadioButtonOnPreRender : System.Web.UI.HtmlControls.HtmlInputRadioButton
{
protected override void OnPreRender(System.EventArgs e)
{
// Run the OnPreRender method on the base class.
base.OnPreRender(e);
// Add a Title attribute.
this.Attributes.Add("title", "Option " + this.Value);
}
}
}
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomHtmlInputRadioButtonOnPreRender
Inherits System.Web.UI.HtmlControls.HtmlInputRadioButton
Protected Overrides Sub OnPreRender(ByVal e As System.EventArgs)
' Run the OnPreRender method on the base class.
MyBase.OnPreRender(e)
' Add a Title attribute.
Me.Attributes.Add("title", "Option " + Me.Value)
End Sub
End Class
Opmerkingen
De OnPreRender methode wordt net voordat het HtmlInputRadioButton besturingselement wordt weergegeven, aangeroepen.
De OnPreRender methode wordt voornamelijk gebruikt door controleontwikkelaars die de functionaliteit van het HtmlInputRadioButton besturingselement uitbreiden.