語言

WebPartDescription 類別

定義

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

提供有關控制項的資訊 WebPart ，您可以在網頁零件控制項目錄中顯示，無需建立該控制項的實例。

public ref class WebPartDescription
public class WebPartDescription
type WebPartDescription = class
Public Class WebPartDescription
繼承
Object
WebPartDescription

範例

以下程式碼範例展示了該 WebPartDescription 類別的程式化使用。 通常，此類型主要由 Web Parts 控制集使用，但此程式碼範例僅展示主要描述屬性的基本程式使用。

程式碼範例包含四個部分：

  • 一個使用者控制功能，允許使用者在網頁上切換顯示模式。

  • 自訂 WebPart 控制。

  • 一個網頁來承載其他控制功能。

  • 說明程式碼範例的運作方式。

程式碼範例的第一部分是使用者控制。 使用者控制的原始碼來自另一個主題。 欲了解更多使用者控制細節，請參閱主題「 攻略：在網頁零件頁面上變更顯示模式」。

<%@ control language="C#" classname="DisplayModeMenuCS"%>
<script runat="server">
  
 // Use a field to reference the current WebPartManager.
  WebPartManager _manager;

  void Page_Init(object sender, EventArgs e)
  {
    Page.InitComplete += new EventHandler(InitComplete);
    
  }  

  void InitComplete(object sender, System.EventArgs e)
  {
    _manager = WebPartManager.GetCurrentWebPartManager(Page);

    String browseModeName = WebPartManager.BrowseDisplayMode.Name;

    // Fill the dropdown with the names of supported display modes.
    foreach (WebPartDisplayMode mode in _manager.SupportedDisplayModes)
    {
      String modeName = mode.Name;
      // Make sure a mode is enabled before adding it.
      if (mode.IsEnabled(_manager))
      {
        ListItem item = new ListItem(modeName, modeName);
        DisplayModeDropdown.Items.Add(item);
      }
    }

    // If shared scope is allowed for this user, display the scope-switching
    // UI and select the appropriate radio button for the current user scope.
    if (_manager.Personalization.CanEnterSharedScope)
    {
      Panel2.Visible = true;
      if (_manager.Personalization.Scope == PersonalizationScope.User)
        RadioButton1.Checked = true;
      else
        RadioButton2.Checked = true;
    }
    
  }
 
  // Change the page to the selected display mode.
  void DisplayModeDropdown_SelectedIndexChanged(object sender, EventArgs e)
  {
    String selectedMode = DisplayModeDropdown.SelectedValue;

    WebPartDisplayMode mode = _manager.SupportedDisplayModes[selectedMode];
    if (mode != null)
      _manager.DisplayMode = mode;
  }

  // Set the selected item equal to the current display mode.
  void Page_PreRender(object sender, EventArgs e)
  {
    ListItemCollection items = DisplayModeDropdown.Items;
    int selectedIndex = 
      items.IndexOf(items.FindByText(_manager.DisplayMode.Name));
    DisplayModeDropdown.SelectedIndex = selectedIndex;
  }

  // Reset all of a user's personalization data for the page.
  protected void LinkButton1_Click(object sender, EventArgs e)
  {
    _manager.Personalization.ResetPersonalizationState();
  }

  // If not in User personalization scope, toggle into it.
  protected void RadioButton1_CheckedChanged(object sender, EventArgs e)
  {
    if (_manager.Personalization.Scope == PersonalizationScope.Shared)
      _manager.Personalization.ToggleScope();
  }

  // If not in Shared scope, and if user is allowed, toggle the scope.
  protected void RadioButton2_CheckedChanged(object sender, EventArgs e)
  {
    if (_manager.Personalization.CanEnterSharedScope && 
        _manager.Personalization.Scope == PersonalizationScope.User)
      _manager.Personalization.ToggleScope();
  }
</script>
<div>
  <asp:Panel ID="Panel1" runat="server" 
    Borderwidth="1" 
    Width="230" 
    BackColor="lightgray"
    Font-Names="Verdana, Arial, Sans Serif" >
    <asp:Label ID="Label1" runat="server" 
      Text="&nbsp;Display Mode" 
      Font-Bold="true"
      Font-Size="8"
      Width="120" 
      AssociatedControlID="DisplayModeDropdown"/>
    <div>
    <asp:DropDownList ID="DisplayModeDropdown" runat="server"  
      AutoPostBack="true" 
      Width="120"
      OnSelectedIndexChanged="DisplayModeDropdown_SelectedIndexChanged" />
    <asp:LinkButton ID="LinkButton1" runat="server"
      Text="Reset User State" 
      ToolTip="Reset the current user's personalization data for the page."
      Font-Size="8"  
      OnClick="LinkButton1_Click" />
    </div>
    <asp:Panel ID="Panel2" runat="server" 
      GroupingText="Personalization Scope"
      Font-Bold="true"
      Font-Size="8" 
      Visible="false" >
      <asp:RadioButton ID="RadioButton1" runat="server" 
        Text="User" 
        AutoPostBack="true"
        GroupName="Scope" OnCheckedChanged="RadioButton1_CheckedChanged" />
      <asp:RadioButton ID="RadioButton2" runat="server" 
        Text="Shared" 
        AutoPostBack="true"
        GroupName="Scope" 
        OnCheckedChanged="RadioButton2_CheckedChanged" />
    </asp:Panel>
  </asp:Panel>
</div>

<%@ control language="vb" classname="DisplayModeMenuVB"%>
<script runat="server">
  ' Use a field to reference the current WebPartManager.
  Dim _manager As WebPartManager

  Sub Page_Init(ByVal sender As Object, ByVal e As EventArgs)
    AddHandler Page.InitComplete, AddressOf InitComplete
  End Sub

  Sub InitComplete(ByVal sender As Object, ByVal e As System.EventArgs)
    _manager = WebPartManager.GetCurrentWebPartManager(Page)
      
    Dim browseModeName As String = WebPartManager.BrowseDisplayMode.Name
      
    ' Fill the dropdown with the names of supported display modes.
    Dim mode As WebPartDisplayMode
    For Each mode In _manager.SupportedDisplayModes
      Dim modeName As String = mode.Name
      ' Make sure a mode is enabled before adding it.
      If mode.IsEnabled(_manager) Then
        Dim item As New ListItem(modeName, modeName)
        DisplayModeDropdown.Items.Add(item)
      End If
    Next mode
      
    ' If shared scope is allowed for this user, display the scope-switching
    ' UI and select the appropriate radio button for the current user scope.
    If _manager.Personalization.CanEnterSharedScope Then
      Panel2.Visible = True
      If _manager.Personalization.Scope = PersonalizationScope.User Then
        RadioButton1.Checked = True
      Else
        RadioButton2.Checked = True
      End If
    End If
   
  End Sub

  ' Change the page to the selected display mode.
  Sub DisplayModeDropdown_SelectedIndexChanged(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    Dim selectedMode As String = DisplayModeDropdown.SelectedValue   
    Dim mode As WebPartDisplayMode = _
      _manager.SupportedDisplayModes(selectedMode)
    If Not (mode Is Nothing) Then
      _manager.DisplayMode = mode
    End If

  End Sub
   
  ' Set the selected item equal to the current display mode.
  Sub Page_PreRender(ByVal sender As Object, ByVal e As EventArgs)
    Dim items As ListItemCollection = DisplayModeDropdown.Items
    Dim selectedIndex As Integer = _
      items.IndexOf(items.FindByText(_manager.DisplayMode.Name))
    DisplayModeDropdown.SelectedIndex = selectedIndex

  End Sub

  ' Reset all of a user's personalization data for the page.
  Protected Sub LinkButton1_Click(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    _manager.Personalization.ResetPersonalizationState()
    
  End Sub

  ' If not in User personalization scope, toggle into it.
  Protected Sub RadioButton1_CheckedChanged(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    If _manager.Personalization.Scope = PersonalizationScope.Shared Then
      _manager.Personalization.ToggleScope()
    End If

  End Sub
   
  ' If not in Shared scope, and if user is allowed, toggle the scope.
  Protected Sub RadioButton2_CheckedChanged(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    If _manager.Personalization.CanEnterSharedScope AndAlso _
      _manager.Personalization.Scope = PersonalizationScope.User Then
      _manager.Personalization.ToggleScope()
    End If

  End Sub

</script>
<div>
  <asp:Panel ID="Panel1" runat="server" 
    Borderwidth="1" 
    Width="230" 
    BackColor="lightgray"
    Font-Names="Verdana, Arial, Sans Serif" >
    <asp:Label ID="Label1" runat="server" 
      Text="&nbsp;Display Mode" 
      Font-Bold="true"
      Font-Size="8"
      Width="120" 
      AssociatedControlID="DisplayModeDropdown"/>
    <div>
    <asp:DropDownList ID="DisplayModeDropdown" runat="server"  
      AutoPostBack="true" 
      Width="120"
      OnSelectedIndexChanged="DisplayModeDropdown_SelectedIndexChanged" />
    <asp:LinkButton ID="LinkButton1" runat="server"
      Text="Reset User State" 
      ToolTip="Reset the current user's personalization data for the page."
      Font-Size="8" 
      OnClick="LinkButton1_Click" />
    </div>
    <asp:Panel ID="Panel2" runat="server" 
      GroupingText="Personalization Scope"
      Font-Bold="true"
      Font-Size="8" 
      Visible="false" >
      <asp:RadioButton ID="RadioButton1" runat="server" 
        Text="User" 
        AutoPostBack="true"
        GroupName="Scope" OnCheckedChanged="RadioButton1_CheckedChanged" />
      <asp:RadioButton ID="RadioButton2" runat="server" 
        Text="Shared" 
        AutoPostBack="true"
        GroupName="Scope" 
        OnCheckedChanged="RadioButton2_CheckedChanged" />
    </asp:Panel>
  </asp:Panel>
</div>

程式碼範例的第二部分是一個自訂 WebPart 控制項。 要執行程式碼範例，你必須編譯這個原始碼。 你可以明確編譯，並將結果組合放到你網站的 Bin 資料夾或全域組合快取中。 或者，你也可以把原始碼放在網站的App_Code資料夾，執行時會動態編譯。 此程式碼範例採用動態編譯方法。 如需示範如何編譯的攻略，請參閱 「攻略：開發與使用自訂網頁伺服器控制項」。

using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Security.Permissions;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  [AspNetHostingPermission(SecurityAction.InheritanceDemand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  public class TextDisplayWebPart : WebPart
  {
    private String _contentText = null;
    TextBox input;
    Label DisplayContent;
    Literal lineBreak;

    [Personalizable(), WebBrowsable]
    public String ContentText
    {
      get { return _contentText; }
      set { _contentText = value; }
    }

    protected override void CreateChildControls()
    {
      Controls.Clear();
      DisplayContent = new Label();
      DisplayContent.BackColor = Color.LightBlue;
      DisplayContent.Text = this.ContentText;
      this.Controls.Add(DisplayContent);

      lineBreak = new Literal();
      lineBreak.Text = @"<br />";
      Controls.Add(lineBreak);

      input = new TextBox();
      this.Controls.Add(input);
      Button update = new Button();
      update.Text = "Set Label Content";
      update.Click += new EventHandler(this.submit_Click);
      this.Controls.Add(update);
    }

    private void submit_Click(object sender, EventArgs e)
    {
      // Update the label string.
      if (!string.IsNullOrEmpty(input.Text))
      {
        _contentText = input.Text + @"<br />";
        input.Text = String.Empty;
        DisplayContent.Text = this.ContentText;
      }
    }
  }
}

Imports System.Collections
Imports System.ComponentModel
Imports System.Drawing
Imports System.Security.Permissions
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts

Namespace Samples.AspNet.VB.Controls

  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class TextDisplayWebPart
    Inherits WebPart
    Private _contentText As String = Nothing
    Private _fontStyle As String = Nothing
    Private input As TextBox
    Private DisplayContent As Label
    Private lineBreak As Literal

    <Personalizable(), WebBrowsable()> _
    Public Property ContentText() As String
      Get
        Return _contentText
      End Get
      Set(ByVal value As String)
        _contentText = value
      End Set
    End Property

    Protected Overrides Sub CreateChildControls()
      Controls.Clear()
      DisplayContent = New Label()
      DisplayContent.BackColor = Color.LightBlue
      DisplayContent.Text = Me.ContentText
      Me.Controls.Add(DisplayContent)

      lineBreak = New Literal()
      lineBreak.Text = "<br />"
      Controls.Add(lineBreak)

      input = New TextBox()
      Me.Controls.Add(input)
      Dim update As New Button()
      update.Text = "Set Label Content"
      AddHandler update.Click, AddressOf Me.submit_Click
      Me.Controls.Add(update)

    End Sub

    Private Sub submit_Click(ByVal sender As Object, _
                             ByVal e As EventArgs)
      ' Update the label string.
      If input.Text <> String.Empty Then
        _contentText = input.Text + "<br />"
        input.Text = String.Empty
        DisplayContent.Text = Me.ContentText
      End If

    End Sub

  End Class

End Namespace

程式碼範例的第三部分是網頁。 在最上方附近有兩個 Register 指令：一個是註冊使用者控制，另一個則是註冊位於你網站App_Code資料夾的自訂 WebPart 控制。 該頁面包含一個<asp:catalogzone>元素，該元素又包含對兩個控制項的宣告式參考：一個名為 的自訂WebPart控制項，以及TextDisplayWebPart一個網頁BulletedList伺服器控制項，執行時會被視為WebPart控制項，因為控制WebPartManager項會以物件包裹它GenericWebPart。 請注意，在該方法的程式碼 Button1_Click 中，目錄中控制項可用的 WebPartDescription 物件 WebPart 會透過此 GetAvailableWebPartDescriptions 方法取得，然後描述細節會全部寫入頁面。

<%@ Page Language="C#" %>
<%@ Register TagPrefix="uc1"
    TagName="DisplayModeMenuCS"
    Src="~/DisplayModeMenuCS.ascx" %>
<%@ Register TagPrefix="aspSample" 
    Namespace="Samples.AspNet.CS.Controls"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

  // <snippet2>
  protected void Button1_Click(object sender, EventArgs e)
  {
    Label1.Text = String.Empty;
    
    WebPartDescriptionCollection descriptions = 
      DeclarativeCatalogPart1.GetAvailableWebPartDescriptions();

    foreach (WebPartDescription desc in descriptions)
    {
      Label1.Text += "ID: " + desc.ID + "<br />" +
        "Title: " + desc.Title + "<br />" +
        "Description: " + desc.Description + "<br />" +
        "ImageUrl: " + desc.CatalogIconImageUrl + "<br />" +
        "<hr />";
    }
  }
  // </snippet2>

  protected void Page_PreRender(object sender, EventArgs e)
  {
    if (mgr1.DisplayMode == WebPartManager.CatalogDisplayMode)
    {
      Button1.Visible = true;
      Label1.Visible = true;
    }
    else
    {
      Button1.Visible = false;
      Label1.Visible = false;
    }
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
  <title>Untitled Page</title>
</head>
<body>
  <form id="form1" runat="server">
    <asp:WebPartManager ID="mgr1" runat="server">
    </asp:WebPartManager>
    <uc1:DisplayModeMenuCS ID="menu1" runat="server" />
    <asp:WebPartZone ID="WebPartZone1" runat="server">
      <ZoneTemplate>
        <asp:Calendar ID="Calendar1" runat="server"></asp:Calendar>
      </ZoneTemplate>
    </asp:WebPartZone>
    <asp:CatalogZone ID="CatalogZone1" runat="server">
      <ZoneTemplate>
        <asp:DeclarativeCatalogPart ID="DeclarativeCatalogPart1" runat="server">
          <WebPartsTemplate>
            <aspSample:TextDisplayWebPart ID="txtDisplayWebPart1" runat="server"
              Title="Text Display"
              Description="Displays entered text in a label control."
              CatalogIconImageUrl="MyWebPartIcon.gif" 
              />
            <asp:BulletedList 
              ID="BulletedList1"
              Runat="server"
              DisplayMode="HyperLink" 
              Title="Favorite Links"
              CatalogIconImageUrl="MyLinksIcon.gif"
              Description="My Favorite Links">
              <asp:ListItem Value="http://msdn.microsoft.com">
                MSDN
              </asp:ListItem>
              <asp:ListItem Value="http://www.asp.net">
                ASP.NET
              </asp:ListItem>
              <asp:ListItem Value="http://www.msn.com">
                MSN
              </asp:ListItem>
            </asp:BulletedList>
          </WebPartsTemplate>
        </asp:DeclarativeCatalogPart>
      </ZoneTemplate>
    </asp:CatalogZone> 
    <hr />
    <asp:Button ID="Button1" runat="server" 
      Text="List WebPartDescription Info" OnClick="Button1_Click" /> 
    <br />
    <asp:Label ID="Label1" runat="server" Text="" />
    <div>
    </div>
  </form>
</body>
</html>

<%@ Page Language="vb" %>
<%@ Register TagPrefix="uc1"
    TagName="DisplayModeMenuVB"
    Src="~/DisplayModeMenuVB.ascx" %>
<%@ Register TagPrefix="aspSample" 
    Namespace="Samples.AspNet.VB.Controls"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

  ' <snippet2>
  Protected Sub Button1_Click(ByVal sender As Object, _
    ByVal e As System.EventArgs)
    
    Label1.Text = String.Empty
        
    Dim descriptions As WebPartDescriptionCollection = _
     DeclarativeCatalogPart1.GetAvailableWebPartDescriptions()
            
    Dim desc As WebPartDescription
        
    For Each desc In descriptions
      Label1.Text += "ID: " & desc.ID & "<br />" & _
        "Title: " & desc.Title & "<br />" & _
        "Description: " & desc.Description & "<br />" & _
        "ImageUrl: " & desc.CatalogIconImageUrl & "<br />" & _
        "<hr />"
    Next
    
  End Sub
  ' </snippet2>

  Protected Sub Page_PreRender(ByVal sender As Object, _
    ByVal e As System.EventArgs)
        
    If mgr1.DisplayMode Is WebPartManager.CatalogDisplayMode Then
      Button1.Visible = True
      Label1.Visible = True
    Else
      Button1.Visible = False
      Label1.Visible = False
    End If
        
  End Sub


</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
  <title>Untitled Page</title>
</head>
<body>
  <form id="form1" runat="server">
    <asp:WebPartManager ID="mgr1" runat="server">
    </asp:WebPartManager>
    <uc1:DisplayModeMenuVB ID="menu1" runat="server" />
    <asp:WebPartZone ID="WebPartZone1" runat="server">
      <ZoneTemplate>
        <asp:Calendar ID="Calendar1" runat="server"></asp:Calendar>
      </ZoneTemplate>
    </asp:WebPartZone>
    <asp:CatalogZone ID="CatalogZone1" runat="server">
      <ZoneTemplate>
        <asp:DeclarativeCatalogPart ID="DeclarativeCatalogPart1" runat="server">
          <WebPartsTemplate>
            <aspSample:TextDisplayWebPart ID="txtDisplayWebPart1" runat="server"
              Title="Text Display"
              Description="Displays entered text in a label control."
              CatalogIconImageUrl="MyWebPartIcon.gif" 
              />
            <asp:BulletedList 
              ID="BulletedList1"
              Runat="server"
              DisplayMode="HyperLink" 
              Title="Favorite Links"
              CatalogIconImageUrl="MyLinksIcon.gif"
              Description="My Favorite Links">
              <asp:ListItem Value="http://msdn.microsoft.com">
                MSDN
              </asp:ListItem>
              <asp:ListItem Value="http://www.asp.net">
                ASP.NET
              </asp:ListItem>
              <asp:ListItem Value="http://www.msn.com">
                MSN
              </asp:ListItem>
            </asp:BulletedList>
          </WebPartsTemplate>
        </asp:DeclarativeCatalogPart>
      </ZoneTemplate>
    </asp:CatalogZone> 
    <hr />
    <asp:Button ID="Button1" runat="server" 
      Text="List WebPartDescription Info" OnClick="Button1_Click" /> 
    <br />
    <asp:Label ID="Label1" runat="server" Text="" />
    <div>
    </div>
  </form>
</body>
</html>

在瀏覽器載入頁面後，使用 顯示模式 下拉選單控制，選擇 目錄 ，將頁面切換為目錄顯示模式。 在目錄中，你應該會看到兩個可新增到頁面上的控制項。 點擊 「List WebPartDescription Information 」按鈕，程式碼會寫出所有可用 WebPartDescription 物件的值到頁面。 這顯示你可以在目錄中取得控制項的描述細節 WebPart ，而不必建立控制項本身的實例。

備註

當 WebPart 控制項顯示在使用者可新增到頁面的控制項目錄中時，需要關於每個控制項的基本資訊。 例如，擁有控制項標題和描述很有用，這樣使用者在瀏覽目錄時就有足夠資訊決定是否要在頁面上新增控制項。 然而，控制項目錄 WebPart 可能包含許多控制項，若必須建立每個 WebPart 控制項的實例以提取並顯示於目錄中的資訊，可能會影響應用程式的效能。

這個 WebPartDescription 類別的存在是為了避免建立控制項實例 WebPart 來取得顯示在控制項目錄中顯示的控制項資訊。 在網頁部分控制集中， WebPartDescription 當頁面處於目錄顯示模式時，物件也會與各種 CatalogPart 控制項一起使用。

該 WebPartDescription 類別有兩個建構子的超載，一個在實例可用時以 WebPart 控制項為參數（建構子）， WebPartDescription 另一個則以多個包含控制項資訊的字串作為參數（ WebPartDescription 建構子）。

該 WebPartDescription 類別也有多個屬性，用以包含控制項的 WebPart 描述資訊。 下表總結了這些 WebPartDescription 屬性，以及每個屬性在控制 WebPart 項中對應的屬性。

Description 屬性 相關的零件控制性質
ID ID
Title Title
Description Description
CatalogIconImageUrl CatalogIconImageUrl

建構函式

名稱 Description
WebPartDescription(String, String, String, String)

透過使用包含控制項描述資訊 WebPart 的多個字串來初始化該類別的新實例。
WebPartDescription(WebPart)

當有控制實例可用時 WebPart ，初始化該類別的新實例。

屬性

名稱 Description
CatalogIconImageUrl

取得一個包含影像路徑的網址，作為控制項圖示 WebPart 。
Description

取得控制組描述 WebPart 的文字。
ID

取得對應 WebPart 控制組的 ID。
Title

取得對應 WebPart 控制項的標題文字。

方法

名稱 Description
Equals(Object)

判斷指定的物件是否等於目前的物件。

(繼承來源 Object)
GetHashCode()

做為預設哈希函式。

(繼承來源 Object)
GetType()

取得目前實例的 Type。

(繼承來源 Object)
MemberwiseClone()

建立目前 Object的淺層複本。

(繼承來源 Object)
ToString()

傳回表示目前 物件的字串。

(繼承來源 Object)

適用於

另請參閱