ImageButton.TagKey 屬性
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。
取得 HtmlTextWriterTag 對應控制點 ImageButton 的值。
protected:
virtual property System::Web::UI::HtmlTextWriterTag TagKey { System::Web::UI::HtmlTextWriterTag get(); };
[System.ComponentModel.Browsable(false)]
protected override System.Web.UI.HtmlTextWriterTag TagKey { get; }
[<System.ComponentModel.Browsable(false)>]
member this.TagKey : System.Web.UI.HtmlTextWriterTag
Protected Overrides ReadOnly Property TagKey As HtmlTextWriterTag
屬性值
一個 HtmlTextWriterTag 列舉值。
- 屬性
範例
以下程式碼範例示範如何在自訂ImageButton控制項中覆寫該TagKey方法,使其始終回傳 Input 標籤。
備註
以下程式碼範例採用單檔案程式碼模型,若直接複製到程式碼背後的檔案中,可能無法正常運作。 程式碼範例的第一部分必須複製到一個副檔名為 .aspx 的空文字檔中。 第二部分必須在 .cs 檔案(C# 的)或 .vb 的檔案(Visual Basic 的)中。 欲了解更多關於網頁表單程式碼模型的資訊,請參見 ASP.NET 網頁表單頁面程式碼模型。
<%@ 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 ImageButton - TagKey - C# Example</title>
<script runat="server">
void ImageButton1_Command(Object sender, CommandEventArgs e)
{
// Redirect to the Microsoft home page.
Response.Redirect("http://www.microsoft.com/");
}
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom ImageButton - TagKey - C# Example</h3>
<aspSample:CustomImageButtonTagKey
id="ImageButton1"
runat="server"
OnCommand="ImageButton1_Command"
AlternateText="Microsoft Home"
ImageUrl="http://www.microsoft.com/homepage/gif/bnr-microsoft.gif" />
</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 ImageButton - TagKey - VB.NET Example</title>
<script runat="server">
Sub ImageButton1_Command(sender As Object, e As CommandEventArgs)
' Redirect to the Microsoft home page.
Response.Redirect("http://www.microsoft.com/")
End Sub
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<h3>Custom ImageButton - TagKey - VB.NET Example</h3>
<aspSample:CustomImageButtonTagKey id="ImageButton1" runat="server"
OnCommand="ImageButton1_Command" AlternateText="Microsoft Home"
ImageUrl="http://www.microsoft.com/homepage/gif/bnr-microsoft.gif" />
</form>
</body>
</html>
using System.Web;
using System.Security.Permissions;
namespace Samples.AspNet.CS.Controls
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
public sealed class CustomImageButtonTagKey : System.Web.UI.WebControls.ImageButton
{
protected override System.Web.UI.HtmlTextWriterTag TagKey
{
get
{
// Specify that only the Input HTML tag can be passed to the HtmlTextWriter.
return System.Web.UI.HtmlTextWriterTag.Input;
}
}
}
}
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomImageButtonTagKey
Inherits System.Web.UI.WebControls.ImageButton
Protected Overrides ReadOnly Property TagKey() As System.Web.UI.HtmlTextWriterTag
Get
' Specify that only the Input HTML tag can be passed to the HtmlTextWriter.
Return System.Web.UI.HtmlTextWriterTag.Input
End Get
End Property
End Class
備註
此 TagKey 屬性主要供控制開發者在從控制項衍生出自訂類別 ImageButton 時使用。
利用該 TagKey 屬性來判斷 HtmlTextWriterTag 控制 ImageButton 項的價值。 此性質覆蓋基礎實作,確保永遠返回 HtmlTextWriterTag.Input。