HideDisabledControlAdapter 類別

定義

public ref class HideDisabledControlAdapter : System::Web::UI::WebControls::Adapters::WebControlAdapter

public class HideDisabledControlAdapter : System.Web.UI.WebControls.Adapters.WebControlAdapter

type HideDisabledControlAdapter = class
    inherit WebControlAdapter

Public Class HideDisabledControlAdapter
Inherits WebControlAdapter

繼承

Object

ControlAdapter

WebControlAdapter

HideDisabledControlAdapter

範例

以下程式碼範例說明如何擴充 HideDisabledControlAdapter 類別，以顯示 Label 啟用與停用狀態下的控制項。 此範例包含三個部分：

• 一個由該 HideDisabledControlAdapter 類別衍生而來的轉接器。

• .aspx檔案，包含 Label 控制項和裝置專屬內容。

• 一個瀏覽器檔案，用來將轉接器連結到裝置類型。

以下程式碼範例示範如何擴充該 HideDisabledControlAdapter 類別。

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

namespace Contoso
{
    [AspNetHostingPermission(
        SecurityAction.Demand, 
        Level = AspNetHostingPermissionLevel.Minimal)]
    [AspNetHostingPermission(
        SecurityAction.InheritanceDemand, 
        Level = AspNetHostingPermissionLevel.Minimal)]
    public class HideDisabledControlContosoAdapter:
        System.Web.UI.WebControls.Adapters.HideDisabledControlAdapter
    {
        // Link the Label control to the adapter.
        protected new System.Web.UI.WebControls.Label Control
        {
            get
            {
                return (System.Web.UI.WebControls.Label)base.Control;
            }
        }

        // Do not render the Contoso controls if Enabled is false.
        protected override void Render(System.Web.UI.HtmlTextWriter writer)
        {
            if (Control.ID.StartsWith("Contoso"))
            {
                if (!Control.Enabled)
                {
                    return;
                }
            }

            base.Render(writer);
        }
    }
}

Imports System.Web
Imports System.Web.UI
Imports System.Security.Permissions

Namespace Contoso
    <AspNetHostingPermission( _
        SecurityAction.Demand, _
        Level:=AspNetHostingPermissionLevel.Minimal)> _
    <AspNetHostingPermission( _
        SecurityAction.InheritanceDemand, _
        Level:=AspNetHostingPermissionLevel.Minimal)> _
    Public Class HideDisabledControlContosoAdapter
        Inherits System.Web.UI.WebControls.Adapters.HideDisabledControlAdapter
    
        Protected Overloads ReadOnly Property Control() As _
            System.Web.UI.WebControls.Label
            Get
                Return CType( _
                    MyBase.Control, _
                    System.Web.UI.WebControls.Label)
            End Get
        End Property

        ' Do not render the control if Enabled is false.
        Protected Overrides Sub Render(ByVal writer As HtmlTextWriter)
            If (Control.ID.StartsWith("Contoso")) Then
                If (Not Control.Enabled) Then
                    Return
                End If
            End If

            MyBase.Render(writer)
        End Sub
    End Class
End Namespace

以下程式碼範例示範如何宣告 Label 具有裝置特定內容的控制項。

<%@ 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 id="Head1" runat="server">
    <title>HideDisabledControl Adapter</title>
    <script runat="server">
        void ServerButtonClick(Object source, EventArgs args)
        {
            if (Button1.Text == "Enable Label")
            {
                ContosoLabel1.Enabled = true;
                Button1.Text = "Disable Label";
                messageLabel.Text = "The label is <b>En</b>abled";
            }
            else
            {
                ContosoLabel1.Enabled = false;
                Button1.Text = "Enable Label";
                messageLabel.Text = "The label is <b>dis</b>abled";
            }
        }
    </script>
</head>
<body style="background-color:silver">
    <form id="Form1" runat="server">
        <asp:Label id="ContosoLabel1"             
            text="Contoso Label" 
            WinCE:text="CE Label"
            BorderWidth="3" 
            BorderStyle="Inset"
            style="FONT-SIZE: xx-small"
            runat="server">
            </asp:Label>
        <br />
        <asp:Button id="Button1" 
            text="Disable Label"
            OnClick="ServerButtonClick" 
            runat="server" />
        <br />    
        <asp:Label id="messageLabel" 
            runat="server" 
            style="FONT-SIZE: xx-small"
            AssociatedControlID="Button1">
            <i>Select the button to disable the label.</i>
        </asp:Label>
    </form>
</body>
</html>

<%@ 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 id="Head1" runat="server">
    <title>HideDisabledControl Adapter</title>
    <script runat="server">
        Sub ServerButtonClick(ByVal source As Object, ByVal args As EventArgs)
            If (Button1.Text.Equals("Enable Label")) Then
                ContosoLabel1.Enabled = True
                Button1.Text = "Disable Label"
                messageLabel.Text = "The label is <b>En</b>abled"
            Else
                ContosoLabel1.Enabled = False
                Button1.Text = "Enable Label"
                messageLabel.Text = "The label is <b>dis</b>abled"
            End If
        End Sub
    </script>
</head>
<body style="background-color:silver">
    <form id="Form1" runat="server">
        <asp:Label id="ContosoLabel1"             
            text="Contoso Label" 
            WinCE:text="CE Label"
            BorderWidth="3" 
            BorderStyle="Inset"
            style="FONT-SIZE: xx-small"
            runat="server">
            </asp:Label>
        <br />
        <asp:Button id="Button1" 
            text="Disable Label"
            OnClick="ServerButtonClick" 
            runat="server" />
        <br />    
        <asp:Label id="messageLabel" 
            runat="server" 
            style="FONT-SIZE: xx-small"
            AssociatedControlID="Button1">
            <i>Select the button to disable the label.</i>
        </asp:Label>
    </form>
</body>
</html>

以下程式碼範例說明如何將 Label 控制項連結到執行 CE .NET Windows 瀏覽器的自訂介面卡。

備註

該 HideDisabledControlAdapter 類別會調整相關 WebControl 控制項，以修改特定瀏覽器的預設標記或行為。 你可以擴充 HideDisabledControlAdapter 類別，進一步自訂控制的渲染 WebControl 。

介面卡是編譯後的 .NET Framework 元件，負責接管頁面或控制項生命週期中的一個或多個階段。 擴展 HideDisabledControlAdapter 類別將提供控制的生命週期階段 WebControl 存取權。 欲了解更多資訊，請參閱 《自適應控制行為架構概述》。

初始的介面卡請求會使 .NET Framework 根據請求瀏覽器的特性搜尋該控制的映射介面卡。 類別使用 HttpBrowserCapabilities 瀏覽器定義檔案來識別用戶端瀏覽器的特性，並將適配器映射到瀏覽器類型。 欲了解更多資訊，請參閱 《自適應控制行為架構概述》。

另請參閱

• WebControlAdapter
• WebControl
• AspNetHostingPermission
• HttpBrowserCapabilities
• 自適應控制行為的架構概述