ValidationSummary.Render(HtmlTextWriter) Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Sends server control content to a provided HtmlTextWriter object, which writes the content to be rendered on the client.
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 -> unitProtected Overrides Sub Render (writer As HtmlTextWriter)Protected Friend Overrides Sub Render (writer As HtmlTextWriter)Parameters
- writer
- HtmlTextWriter
The output stream that renders HTML content to the client.
Examples
The following code example demonstrates how to override the Render method in a custom server control so that the ValidationSummary control is surrounded by a Small tag.
Important
This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.
<%@ 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 ValidationSummary - Render - C# Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom ValidationSummary - Render - C# Example</h3>
<table id="Table1" cellpadding="4" cellspacing="0">
<tr>
<td>
<table id="Table2" cellpadding="4" cellspacing="0" style="background-color:#eeeeee">
<tr>
<td colspan="3"><b>Credit Card Information</b> </td>
</tr>
<tr>
<td align="right">Card Type: </td>
<td>
<asp:RadioButtonList id="RadioButtonList1" runat="server" RepeatLayout="Flow">
<asp:ListItem>MasterCard</asp:ListItem>
<asp:ListItem>Visa</asp:ListItem>
</asp:RadioButtonList>
</td>
<td align="center" rowspan="1">
<asp:RequiredFieldValidator
id="RequiredFieldValidator1"
runat="server"
ErrorMessage="Card Type"
Width="100%"
Display="Static"
ControlToValidate="RadioButtonList1">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td align="right">Card Number: </td>
<td><asp:TextBox id="TextBox1" runat="server"></asp:TextBox></td>
<td>
<asp:RequiredFieldValidator
id="RequiredFieldValidator2"
runat="server"
ErrorMessage="Card Number"
Width="100%"
Display="Static"
ControlToValidate="TextBox1">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td></td>
<td><asp:Button id="Button1" runat="server" text="Validate"></asp:Button></td>
<td></td>
</tr>
</table>
</td>
</tr>
<tr>
<td valign="top">
<aspSample:CustomValidationSummaryRender
id="ValidationSummary1"
runat="server"
DisplayMode="BulletList"
HeaderText="You must enter a value in the following fields:" />
</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 ValidationSummary - Render - VB.NET Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom ValidationSummary - Render - VB.NET Example</h3>
<table id="Table1" cellpadding="4" cellspacing="0">
<tr>
<td>
<table id="Table2" cellpadding="4" cellspacing="0" style="background-color:#eeeeee">
<tr>
<td colspan="3"><b>Credit Card Information</b> </td>
</tr>
<tr>
<td align="right">Card Type: </td>
<td><asp:RadioButtonList id="RadioButtonList1" runat="server" RepeatLayout="Flow">
<asp:ListItem>MasterCard</asp:ListItem>
<asp:ListItem>Visa</asp:ListItem>
</asp:RadioButtonList>
</td>
<td align="center" rowspan="1">
<asp:RequiredFieldValidator id="RequiredFieldValidator1"
runat="server" ErrorMessage="Card Type" Width="100%"
Display="Static" ControlToValidate="RadioButtonList1">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td align="right">Card Number: </td>
<td><asp:TextBox id="TextBox1" runat="server"></asp:TextBox></td>
<td>
<asp:RequiredFieldValidator id="RequiredFieldValidator2"
runat="server" ErrorMessage="Card Number" Width="100%"
Display="Static" ControlToValidate="TextBox1">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td></td>
<td><asp:Button id="Button1" runat="server" text="Validate"></asp:Button></td>
<td></td>
</tr>
</table>
</td>
</tr>
<tr>
<td valign="top">
<aspSample:CustomValidationSummaryRender
id="ValidationSummary1" runat="server" DisplayMode="BulletList"
HeaderText="You must enter a value in the following fields:" />
</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 CustomValidationSummaryRender : System.Web.UI.WebControls.ValidationSummary
{
protected override void Render(System.Web.UI.HtmlTextWriter writer)
{
// Write out begining Small HTML tag.
writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Small);
// Call the base class's Render method.
base.Render(writer);
// Write out ending Small HTML tag.
writer.RenderEndTag();
}
}
}
Imports System.Web
Imports System.Security.Permissions
Namespace Samples.AspNet.VB.Controls
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomValidationSummaryRender
Inherits System.Web.UI.WebControls.ValidationSummary
Protected Overrides Sub Render(ByVal writer As System.Web.UI.HtmlTextWriter)
' Write out begining Small HTML tag.
writer.RenderBeginTag(System.Web.UI.HtmlTextWriterTag.Small)
' Call the base class's Render method.
MyBase.Render(writer)
' Write out ending Small HTML tag.
writer.RenderEndTag()
End Sub
End Class
End Namespace
Applies to
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