RangeValidator.AddAttributesToRender(HtmlTextWriter) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
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
下列程式代碼範例示範如何在自定義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