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RangeValidator.AddAttributesToRender(HtmlTextWriter) 方法

  • 參考

定義

命名空間:
System.Web.UI.WebControls
組件:
System.Web.dll

將需要呈現給控制項的 HTML 屬性和樣式加入至指定的 HtmlTextWriter 物件中。

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)

參數

writer
HtmlTextWriter

HtmlTextWriter，代表要在用戶端呈現 HTML 內容的輸出資料流。

範例

下列程式碼範例示範如何在自訂伺服器控制項中覆寫 AddAttributesToRender 方法， RangeValidator 讓文字一律顯示為粗體。

重要

這個範例有一個可接受使用者輸入的文字方塊，這可能會造成安全性威脅。 根據預設，ASP.NET Web 網頁會驗證使用者輸入未包含指令碼或 HTML 項目。 如需詳細資訊，請參閱 Script Exploits Overview (指令碼攻擊概觀)。

<%@ 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 RangeValidator - AddAttributesToRender - C# Example</title>
    <script runat="server">
      void ButtonClick(Object sender, EventArgs e)
      {
        if (Page.IsValid)
        {
          Label1.Text="Page is valid.";
        }
        else
        {
          Label1.Text="Page is not valid!!";
        }
      }
    </script>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">
      <h3>Custom RangeValidator - AddAttributesToRender - C# Example</h3>

      Enter a number from 1 to 10:<br />
      <asp:TextBox id="TextBox1" Runat="server" />

      <aspSample:CustomRangeValidatorAddAttributesToRender 
        id="RangeValidator1" 
        runat="server" 
        ControlToValidate="TextBox1" 
        MinimumValue="1" 
        MaximumValue="10" 
        Type="Integer" 
        EnableClientScript="false" 
        Text="The value must be from 1 to 10!" />
        
      <br />
      <br />
      <asp:Button id="Button1" Text="Submit" OnClick="ButtonClick" runat="server" /><br />
      <br />

      <asp:Label id="Label1" runat="server" />
    </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 RangeValidator - AddAttributesToRender - VB.NET Example</title>
        <script runat="server">
            Sub ButtonClick(sender As Object, e As EventArgs)
                If Page.IsValid Then
                    Label1.Text="Page is valid."
                Else
                    Label1.Text="Page is not valid!"
                End If
            End Sub
        </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom RangeValidator - AddAttributesToRender - VB.NET Example</h3>

            Enter a number from 1 to 10:<br />
            <asp:TextBox id="TextBox1" Runat="server" />
            
            <aspSample:CustomRangeValidatorAddAttributesToRender id="RangeValidator1" runat="server" 
             ControlToValidate="TextBox1" MinimumValue="1" MaximumValue="10" Type="Integer" 
             EnableClientScript="false" Text="The value must be from 1 to 10!" /><br />
             <br />
             
            <asp:Button id="Button1" Text="Submit" OnClick="ButtonClick" runat="server" /><br />
             <br />
             
            <asp:Label id="Label1" runat="server"/>
        </form>
    </body>
</html>

using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomRangeValidatorAddAttributesToRender : System.Web.UI.WebControls.RangeValidator
  {
    protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer)
    {
      // Show the Validation text as Bold 
      writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.FontWeight, "bold");
      
      // Call the base 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 CustomRangeValidatorAddAttributesToRender
        Inherits System.Web.UI.WebControls.RangeValidator

        Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)

            ' Show the Validation text as Bold 
            writer.AddStyleAttribute(System.Web.UI.HtmlTextWriterStyle.FontWeight, "bold")

            ' Call the base AddAttributesToRender method.
            MyBase.AddAttributesToRender(writer)
        End Sub
    End Class
End Namespace

適用於