RequiredFieldValidator.AddAttributesToRender(HtmlTextWriter) Méthode
Définition
Important
Certaines informations portent sur la préversion du produit qui est susceptible d’être en grande partie modifiée avant sa publication. Microsoft exclut toute garantie, expresse ou implicite, concernant les informations fournies ici.
Ajoute les attributs et les styles HTML qui doivent être rendus pour le contrôle à l'objet HtmlTextWriter spécifié.
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)
Paramètres
- writer
- HtmlTextWriter
HtmlTextWriter qui représente le flux de sortie utilisé pour restituer le contenu HTML sur le client.
Exemples
L’exemple de code suivant montre comment remplacer la AddAttributesToRender méthode dans un contrôle serveur personnalisé afin que le RequiredFieldValidator message d’erreur s’affiche toujours en gras.
Important
Cet exemple comprend une zone de texte qui accepte une entrée d'utilisateur, ce qui constitue une menace potentielle pour la sécurité. Par défaut, les pages web ASP.NET vérifient que l’entrée d’utilisateur n’inclut pas de script ou d’éléments HTML. Pour plus d’informations, consultez Vue d’ensemble des attaques de script.
<%@ 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 RequiredFieldValidator - AddAttributesToRender - C# Example</title>
<script runat="server">
void Button1_Click(Object sender, EventArgs e)
{
if (Page.IsValid)
{
Label1.Text = "Required field is filled!";
}
else
{
Label1.Text = "Required field is empty!";
}
}
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom RequiredFieldValidator - AddAttributesToRender - C# Example</h3>
<table border="0" cellpadding="4" cellspacing="0">
<tr valign="top">
<td colspan="3">
<asp:Label ID="Label1" runat="server" Text="Fill in the required field below" />
</td>
</tr>
<tr>
<td align="right">Card Number:</td>
<td>
<asp:TextBox id="TextBox1" runat="server" />
</td>
<td>
<aspSample:CustomRequiredFieldValidatorAddAttributesToRender
id="RequiredFieldValidator1"
runat="server"
ControlToValidate="TextBox1"
Display="Static"
ErrorMessage="Required" />
</td>
</tr>
<tr>
<td> </td>
<td>
<asp:Button id="Button1" runat="server" Text="Validate" OnClick="Button1_Click" />
</td>
<td> </td>
</tr>
</table>
</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 RequiredFieldValidator - AddAttributesToRender - VB.NET Example</title>
<script runat="server">
Sub Button1_Click(sender As Object, e As EventArgs)
If Page.IsValid Then
Label1.Text = "Required field is filled!"
Else
Label1.Text = "Required field is empty!"
End If
End Sub
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom RequiredFieldValidator - AddAttributesToRender - VB.NET Example</h3>
<table border="0" cellpadding="4" cellspacing="0">
<tr valign="top">
<td colspan="3">
<asp:Label ID="Label1" runat="server"
Text="Fill in the required field below" />
</td>
</tr>
<tr>
<td align="right">Card Number:</td>
<td>
<asp:TextBox id="TextBox1" runat="server" />
</td>
<td>
<aspSample:CustomRequiredFieldValidatorAddAttributesToRender id="RequiredFieldValidator1"
runat="server" ControlToValidate="TextBox1" Display="Static" ErrorMessage="Required" />
</td>
</tr>
<tr>
<td> </td>
<td>
<asp:Button id="Button1" runat="server" Text="Validate"
OnClick="Button1_Click" />
</td>
<td> </td>
</tr>
</table>
</form>
</body>
</html>
using System.Web;
using System.Security.Permissions;
namespace Samples.AspNet.CS.Controls
{
[AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
public sealed class CustomRequiredFieldValidatorAddAttributesToRender : System.Web.UI.WebControls.RequiredFieldValidator
{
protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer)
{
// Show the RequiredFieldValidator's error message as bold.
writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.FontWeight, "bold");
// 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 CustomRequiredFieldValidatorAddAttributesToRender
Inherits System.Web.UI.WebControls.RequiredFieldValidator
Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)
' Show the RequiredFieldValidator's error message as bold.
writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.FontWeight, "bold")
' Call the Base's AddAttributesToRender method.
MyBase.AddAttributesToRender(writer)
End Sub
End Class
End Namespace