ImageButton.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 ImageButton 的屬性加入輸出資料流中，以便在用戶端呈現。
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 -> unitProtected Overrides Sub AddAttributesToRender (writer As HtmlTextWriter)參數
- writer
- HtmlTextWriter
要在用戶端呈現的輸出資料流。
範例
下列程式代碼範例示範如何覆寫 AddAttributesToRender 自定義伺服器控制項中的方法， ImageButton 讓文字一律以細框線顯示。
注意
下列程式代碼範例會使用單一檔案程式代碼模型，如果直接複製到程式代碼後置檔案，可能無法正常運作。 此程式代碼範例的第一個部分必須複製到具有.aspx擴展名的空白文本檔中。 第二個部分必須儲存為程式代碼檔案， (C# .cs或 Visual Basic) .vb。 如需 Web Forms 程式代碼模型的詳細資訊，請參閱 ASP.NET Web Forms 頁面代碼模型。
<%@ 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 - AddAttributesToRender - 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 - AddAttributesToRender - C# Example</h3>
<aspSample:CustomImageButtonAddAttributesToRender 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 - AddAttributesToRender - 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 - AddAttributesToRender - VB.NET Example</h3>
<aspSample:CustomImageButtonAddAttributesToRender 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 CustomImageButtonAddAttributesToRender : System.Web.UI.WebControls.ImageButton
{
protected override void AddAttributesToRender(System.Web.UI.HtmlTextWriter writer)
{
// Show the ImageButton with a thin border.
writer.AddStyleAttribute("border-width","thin");
// Call the Base's AddAttributesToRender method.
base.AddAttributesToRender(writer);
}
}
}
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomImageButtonAddAttributesToRender
Inherits System.Web.UI.WebControls.ImageButton
Protected Overrides Sub AddAttributesToRender(ByVal writer As System.Web.UI.HtmlTextWriter)
' Show the ImageButton with a thin border.
writer.AddStyleAttribute("border-width", "thin")
' Call the Base's AddAttributesToRender method.
MyBase.AddAttributesToRender(writer)
End Sub
End Class
備註
從控件衍生自定義類別時，方法 OnPreRender 主要是由控件開發人員使用 ImageButton 。
