CompareValidator.AddAttributesToRender(HtmlTextWriter) 方法

定义

将此控件的属性添加到输出流中,以便在客户端上呈现。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)

参数

writer
HtmlTextWriter

包含用于在客户端上进行呈现的输出流的 HtmlTextWriterA HtmlTextWriter that contains the output stream for rendering on the client.

示例

下面的代码示例演示如何重写 AddAttributesToRender 自定义服务器控件中的方法,以便 CompareValidator 错误消息始终显示为粗体。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.

重要

此示例具有一个接受用户输入的文本框,这是一个潜在的安全威胁。This example has a text box that accepts user input, which is a potential security threat. 默认情况下,ASP.NET 网页验证用户输入是否不包含脚本或 HTML 元素。By default, ASP.NET Web pages validate that user input does not include script or HTML elements. 有关详细信息,请参阅脚本侵入概述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

适用于