CompareValidator.AddAttributesToRender(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.
Adds the attributes of this control to the output stream for rendering on the client.
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)
Parameters
- writer
- HtmlTextWriter
A HtmlTextWriter that contains the output stream for rendering on the client.
Examples
The following code example demonstrates how to override the AddAttributesToRender method in a custom server control so that the CompareValidator error message always appears in bold.
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#" %>
<!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 CompareValidator - AddAttributesToRender - C# Example</title>
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
// Run the Page Validate method in order to force
// the CompareValidate to show it's error message.
Page.Validate();
}
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom CompareValidator - AddAttributesToRender - C# Example</h3>
<asp:TextBox id="TextBox1" runat="server">123</asp:TextBox><br />
<asp:TextBox id="TextBox2" runat="server">456</asp:TextBox>
<aspSample:CustomCompareValidatorAddAttributesToRender
id="CompareValidator1"
runat="server"
ErrorMessage="Value in TextBox2 does not match value in TextBox1."
Display="Dynamic"
ControlToCompare="TextBox2"
ControlToValidate="TextBox1" /><br />
<asp:Button id="Button1" runat="server" Text="Button" />
</form>
</body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ Page language="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 CompareValidator - AddAttributesToRender - VB.NET Example</title>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom CompareValidator - AddAttributesToRender - C# Example</h3>
<asp:TextBox id="TextBox1" runat="server">123</asp:TextBox><br />
<asp:TextBox id="TextBox2" runat="server">456</asp:TextBox>
<aspSample:CustomCompareValidatorAddAttributesToRender
id="CompareValidator1" runat="server"
ErrorMessage="Value in TextBox2 does not match value in TextBox1."
Display="Dynamic" ControlToCompare="TextBox2" ControlToValidate="TextBox1" /><br />
<asp:Button id="Button1" runat="server" Text="Button" />
</form>
</body>
</html>
using System.Web;
using System.Security.Permissions;
namespace Samples.AspNet.CS.Controls
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
public sealed class CustomCompareValidatorAddAttributesToRender : System.Web.UI.WebControls.CompareValidator
{
protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer)
{
// Show the CompareValidator'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 CustomCompareValidatorAddAttributesToRender
Inherits System.Web.UI.WebControls.CompareValidator
Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)
' Show the CompareValidator'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