ConnectionPoint 類別

定義

做為定義連接點物件的基底類別,這些物件可讓 Web 組件連接中的消費者控制項和提供者控制項共用資料。

public ref class ConnectionPoint abstract
public abstract class ConnectionPoint
type ConnectionPoint = class
Public MustInherit Class ConnectionPoint
繼承
ConnectionPoint
衍生

範例

下列程式碼範例示範如何建立包含必要 ConnectionPoint 物件的網頁元件連線。 因為類別 ConnectionPoint 是抽象基類,所以其子類別的實例-- ProviderConnectionPointConsumerConnectionPoint --是用來形成連接的實際物件。

此範例有四個部分:

  • 使用者控制項,可讓您變更頁面上的網頁元件顯示模式。

  • 介面的原始程式碼,以及 WebPart 兩個做為連接提供者和取用者的控制項。

  • 裝載所有控制項並執行程式碼範例的網頁。

  • 如何執行範例頁面的說明。

此程式碼範例的第一個部分是使用者控制項,可讓使用者變更網頁上的顯示模式。 將下列原始程式碼儲存至 .ascx 檔案,為其提供指派給 Src 這個使用者控制項之 指示詞之 屬性的 Register 檔案名,其位於主控網頁頂端附近。 如需此控制項中顯示模式和原始程式碼描述的詳細資訊,請參閱逐步解說 :變更網頁元件頁面上的顯示模式

<%@ 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=" Display Mode" 
      Font-Bold="true"
      Font-Size="8"
      Width="120" 
      AssociatedControlID="DisplayModeDropdown"/>
    <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" />
    <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=" Display Mode" 
      Font-Bold="true"
      Font-Size="8"
      Width="120" 
      AssociatedControlID="DisplayModeDropdown"/>
    <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" />
    <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>

程式碼範例的第二個部分是介面和控制項的原始程式碼。 原始程式檔包含名為 的 IZipCode 簡單介面。 另外 WebPart 還有名為 ZipCodeWebPart 的類別可實作 介面,並做為提供者控制項。 其 ProvideIZipCode 方法是實作介面唯一成員的回呼方法。 方法只會傳回 介面的實例。 請注意,方法會以其 ConnectionProvider 中繼資料中的 屬性標示。 這是將方法識別為提供者連接點回呼方法的機制。 另一個 WebPart 類別的名稱為 WeatherWebPart ,其會作為連接的取用者。 這個類別具有名為 GetZipCode 的方法,可從提供者控制項取得介面的 IZipCode 實例。 請注意,這個方法會標示為取用者的連接點方法 ConnectionConsumer 及其中繼資料中的屬性。 這是識別取用者控制項中連接點方法的機制。

若要執行程式碼範例,您必須編譯此原始程式碼。 您可以明確地編譯它,並將產生的元件放在網站的 Bin 資料夾或全域組件快取中。 或者,您可以將原始程式碼放在月臺的 App_Code 資料夾中,其將在執行時間動態編譯。 此程式碼範例會使用動態編譯。 如需示範如何編譯的逐步解說,請參閱逐步解說 :開發和使用自訂 Web 服務器控制項

namespace Samples.AspNet.CS.Controls
{
  using System;
  using System.Web;
  using System.Web.Security;
  using System.Security.Permissions;
  using System.Web.UI;
  using System.Web.UI.WebControls;
  using System.Web.UI.WebControls.WebParts;

  [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  [AspNetHostingPermission(SecurityAction.InheritanceDemand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  public interface IZipCode
  {
    string ZipCode { get; set;}
  }

  [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  [AspNetHostingPermission(SecurityAction.InheritanceDemand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  public class ZipCodeWebPart : WebPart, IZipCode
  {
    string zipCodeText = String.Empty;
    TextBox input;
    Button send;

    public ZipCodeWebPart()
    {
    }

    // Make the implemented property personalizable to save 
    // the Zip Code between browser sessions.
    [Personalizable()]
    public virtual string ZipCode
    {
      get { return zipCodeText; }
      set { zipCodeText = value; }
    }

    // This is the callback method that returns the provider.
    [ConnectionProvider("Zip Code Provider", "ZipCodeProvider")]
    public IZipCode ProvideIZipCode()
    {
      return this;
    }

    protected override void CreateChildControls()
    {
      Controls.Clear();
      input = new TextBox();
      this.Controls.Add(input);
      send = new Button();
      send.Text = "Enter 5-digit Zip Code";
      send.Click += new EventHandler(this.submit_Click);
      this.Controls.Add(send);
    }

    private void submit_Click(object sender, EventArgs e)
    {
      if (!string.IsNullOrEmpty(input.Text))
      {
        zipCodeText = Page.Server.HtmlEncode(input.Text);
        input.Text = String.Empty;
      }
    }
  }

  [AspNetHostingPermission(SecurityAction.Demand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  [AspNetHostingPermission(SecurityAction.InheritanceDemand,
    Level = AspNetHostingPermissionLevel.Minimal)]
  public class WeatherWebPart : WebPart
  {
    private IZipCode _provider;
    string _zipSearch;
    Label DisplayContent;

    // This method is identified by the ConnectionConsumer 
    // attribute, and is the mechanism for connecting with 
    // the provider. 
    [ConnectionConsumer("Zip Code Consumer", "ZipCodeConsumer")]
    public void GetIZipCode(IZipCode Provider)
    {
      _provider = Provider;
    }
    
    protected override void OnPreRender(EventArgs e)
    {
      EnsureChildControls();

      if (this._provider != null)
      {
        _zipSearch = _provider.ZipCode.Trim();
        DisplayContent.Text = "My Zip Code is:  " + _zipSearch;
      }
    }

    protected override void CreateChildControls()
    {
      Controls.Clear();
      DisplayContent = new Label();
      this.Controls.Add(DisplayContent);
    }
  }
}
Imports System.Web
Imports System.Web.Security
Imports System.Security.Permissions
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 Interface IZipCode

    Property ZipCode() As String

  End Interface

  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class ZipCodeWebPart
    Inherits WebPart
    Implements IZipCode
    Private zipCodeText As String = String.Empty
    Private input As TextBox
    Private send As Button

    Public Sub New()
    End Sub

    ' Make the implemented property personalizable to save 
    ' the Zip Code between browser sessions.
    <Personalizable()> _
    Public Property ZipCode() As String _
      Implements IZipCode.ZipCode

      Get
        Return zipCodeText
      End Get
      Set(ByVal value As String)
        zipCodeText = value
      End Set
    End Property

    ' This is the callback method that returns the provider.
    <ConnectionProvider("Zip Code Provider", "ZipCodeProvider")> _
    Public Function ProvideIZipCode() As IZipCode
      Return Me
    End Function


    Protected Overrides Sub CreateChildControls()
      Controls.Clear()
      input = New TextBox()
      Me.Controls.Add(input)
      send = New Button()
      send.Text = "Enter 5-digit Zip Code"
      AddHandler send.Click, AddressOf Me.submit_Click
      Me.Controls.Add(send)

    End Sub


    Private Sub submit_Click(ByVal sender As Object, _
      ByVal e As EventArgs)

      If input.Text <> String.Empty Then
        zipCodeText = Page.Server.HtmlEncode(input.Text)
        input.Text = String.Empty
      End If

    End Sub

  End Class

  <AspNetHostingPermission(SecurityAction.Demand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  <AspNetHostingPermission(SecurityAction.InheritanceDemand, _
    Level:=AspNetHostingPermissionLevel.Minimal)> _
  Public Class WeatherWebPart
    Inherits WebPart
    Private _provider As IZipCode
    Private _zipSearch As String
    Private DisplayContent As Label

    ' This method is identified by the ConnectionConsumer 
    ' attribute, and is the mechanism for connecting with 
    ' the provider. 
    <ConnectionConsumer("Zip Code Consumer", "ZipCodeConsumer")> _
    Public Sub GetIZipCode(ByVal Provider As IZipCode)
      _provider = Provider
    End Sub


    Protected Overrides Sub OnPreRender(ByVal e As EventArgs)
      EnsureChildControls()

      If Not (Me._provider Is Nothing) Then
        _zipSearch = _provider.ZipCode.Trim()
                DisplayContent.Text = "My Zip Code is:  " + _zipSearch
      End If

    End Sub

    Protected Overrides Sub CreateChildControls()
      Controls.Clear()
      DisplayContent = New Label()
      Me.Controls.Add(DisplayContent)

    End Sub

  End Class

End Namespace

程式碼範例的第三個部分是網頁。 靠近頂端的 指示詞是 Register 註冊形成連線的自訂控制項,以及讓使用者變更頁面上顯示模式的使用者控制項。 連接本身是以宣告方式在頁面上的 <staticconnections> 元素內建立。 您也可以以程式設計方式建立連線;用於執行此作業的程式碼包含在 方法中 Button1_Click 。 無論是以宣告方式或以程式設計方式建立連接,都必須同時為提供者和取用者指定連接點。 方法 Button2_ClickConnectionPoint 存取提供者和取用者的物件,並將其部分屬性值寫入頁面中的標籤。

<%@ 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">

  protected void Button1_Click(object sender, EventArgs e)
  {
    ProviderConnectionPoint provPoint =
      mgr.GetProviderConnectionPoints(zip1)["ZipCodeProvider"];
    ConsumerConnectionPoint connPoint =
      mgr.GetConsumerConnectionPoints(weather1)["ZipCodeConsumer"];
      
    if(mgr.CanConnectWebParts(zip1, provPoint, weather1, connPoint))
      mgr.ConnectWebParts(zip1, provPoint, weather1, connPoint);
  
  }  
  protected void Button2_Click(object sender, EventArgs e)
  {
    WebPartConnection conn = mgr.Connections[0];
    
    lblConn.Text = "<h2>Connection Point Details</h2>" + 
       "<h3>Provider Connection Point</h3>" + 
       "  Display name: " + conn.ProviderConnectionPoint.DisplayName + 
       "<br />" + 
       "  ID: " + conn.ProviderConnectionPoint.ID + 
       "<br />" + 
       "  Interface type: " + 
        conn.ProviderConnectionPoint.InterfaceType.ToString() + 
       "<br />" + 
       "  Control type: " + conn.ProviderConnectionPoint.ControlType.ToString() + 
       "<br />" + 
       "  Allows multiple connections: " + 
          conn.ProviderConnectionPoint.AllowsMultipleConnections.ToString() + 
       "<br />" + 
       "  Enabled: " + conn.ProviderConnectionPoint.GetEnabled(zip1).ToString() + 
       "<hr />" + 
       "<h3>Consumer Connection Point</h3>" + 
       "  Display name: " + conn.ConsumerConnectionPoint.DisplayName + 
       "<br />" + 
       "  ID: " + conn.ConsumerConnectionPoint.ID + 
       "<br />" + 
       "  Interface type: " + conn.ConsumerConnectionPoint.InterfaceType.ToString() + 
       "<br />" + 
       "  Control type: " + conn.ConsumerConnectionPoint.ControlType.ToString() + 
       "<br />" + 
       "  Allows multiple connections: " + 
          conn.ConsumerConnectionPoint.AllowsMultipleConnections.ToString() + 
       "<br />" + 
       "  Enabled: " + conn.ConsumerConnectionPoint.GetEnabled(zip1).ToString();
  }

  protected void Page_Load(object sender, EventArgs e)
  {
    lblConn.Text = String.Empty;
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:WebPartManager ID="mgr" runat="server" >
        <StaticConnections>
          <asp:WebPartConnection ID="conn1"
            ConsumerConnectionPointID="ZipCodeConsumer"
            ConsumerID="weather1" 
            ProviderConnectionPointID="ZipCodeProvider" 
            ProviderID="zip1" />
        </StaticConnections>      
      </asp:WebPartManager>
      <uc1:displaymodemenucs id="menu1" runat="server" />
      <asp:WebPartZone ID="WebPartZone1" runat="server">
        <ZoneTemplate>
          <aspSample:ZipCodeWebPart ID="zip1" runat="server"
            Title="Zip Code Provider"  />
          <aspSample:WeatherWebPart ID="weather1" runat="server" 
            Title="Zip Code Consumer" />
        </ZoneTemplate>
      </asp:WebPartZone>
      <asp:ConnectionsZone ID="ConnectionsZone1" runat="server">
      </asp:ConnectionsZone>
      <asp:Button ID="Button1" runat="server" 
        Text="Dynamic Connection" 
        OnClick="Button1_Click" />      
      <br />
      <asp:Button ID="Button2" runat="server" 
        Text="Connection Point Details" 
        OnClick="Button2_Click" />
      <br />
      <asp:Label ID="lblConn" runat="server" />
    </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">

  Protected Sub Button1_Click(ByVal sender As Object, _
    ByVal e As System.EventArgs)

    Dim provPoint As ProviderConnectionPoint = _
      mgr.GetProviderConnectionPoints(zip1)("ZipCodeProvider")
    Dim connPoint As ConsumerConnectionPoint = _
      mgr.GetConsumerConnectionPoints(weather1)("ZipCodeConsumer")

    If mgr.CanConnectWebParts(zip1, provPoint, weather1, connPoint) Then
      mgr.ConnectWebParts(zip1, provPoint, weather1, connPoint)
    End If
    
  End Sub
  
  Protected Sub Button2_Click(ByVal sender As Object, _
    ByVal e As System.EventArgs)
    
    Dim conn As WebPartConnection = mgr.Connections(0)

    lblConn.Text = "<h2>Connection Point Details</h2>" & _
      "<h3>Provider Connection Point</h3>" & _
      "  Display name: " & conn.ProviderConnectionPoint.DisplayName & _
      "<br />" & _
      "  ID: " & conn.ProviderConnectionPoint.ID & _
      "<br />" & _
      "  Interface type: " & conn.ProviderConnectionPoint.InterfaceType.ToString() & _
      "<br />" & _
      "  Control type: " & conn.ProviderConnectionPoint.ControlType.ToString() & _
      "<br />" & _
      "  Allows multiple connections: " & _
        conn.ProviderConnectionPoint.AllowsMultipleConnections.ToString() & _
      "<br />" & _
      "  Enabled: " & conn.ProviderConnectionPoint.GetEnabled(zip1).ToString() & _
      "<hr />" & _
      "<h3>Consumer Connection Point</h3>" & _
      "  Display name: " & conn.ConsumerConnectionPoint.DisplayName & _
      "<br />" & _
      "  ID: " & conn.ConsumerConnectionPoint.ID & _
      "<br />" & _
      "  Interface type: " & conn.ConsumerConnectionPoint.InterfaceType.ToString() & _
      "<br />" & _
      "  Control type: " & conn.ConsumerConnectionPoint.ControlType.ToString() & _
      "<br />" & _
      "  Allows multiple connections: " & _
        conn.ConsumerConnectionPoint.AllowsMultipleConnections.ToString() & _
      "<br />" & _
      "  Enabled: " & conn.ConsumerConnectionPoint.GetEnabled(zip1).ToString()
          
  End Sub

  Protected Sub Page_Load(ByVal sender As Object, _
    ByVal e As System.EventArgs)
    lblConn.Text = String.Empty
  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">
    <div>
      <asp:WebPartManager ID="mgr" runat="server" >
        <StaticConnections>
          <asp:WebPartConnection ID="conn1"
            ConsumerConnectionPointID="ZipCodeConsumer"
            ConsumerID="weather1" 
            ProviderConnectionPointID="ZipCodeProvider" 
            ProviderID="zip1" />
        </StaticConnections>      
      </asp:WebPartManager>
      <uc1:displaymodemenuvb id="menu1" runat="server" />
      <asp:WebPartZone ID="WebPartZone1" runat="server">
        <ZoneTemplate>
          <aspSample:ZipCodeWebPart ID="zip1" runat="server"
            Title="Zip Code Provider"  />
          <aspSample:WeatherWebPart ID="weather1" runat="server" 
            Title="Zip Code Consumer" />
        </ZoneTemplate>
      </asp:WebPartZone>
      <asp:ConnectionsZone ID="ConnectionsZone1" runat="server">
      </asp:ConnectionsZone>
      <asp:Button ID="Button1" runat="server" 
        Text="Dynamic Connection" 
        OnClick="Button1_Click" />      
      <br />
      <asp:Button ID="Button2" runat="server" 
        Text="Connection Point Details" 
        OnClick="Button2_Click" />
      <br />
      <asp:Label ID="lblConn" runat="server" />
    </div>
    </form>
</body>
</html>

在瀏覽器中載入頁面之後,按一下 [ 連接點詳細資料] 按鈕。 在宣告式連接中建立的提供者和取用者連接點相關資訊隨即出現。 接下來,使用 [顯示模式 ] 下拉式控制項,將頁面切換為連線模式。 在標題列中) 向下箭號所代表的 WebPart 其中一個 (控制項動詞功能表上,按一下連接動詞命令。 連接 UI 隨即出現,由頁面宣告的 <asp:connectionszone> 控制項自動建立。 按一下 [ 中斷連線 ] 按鈕以終止現有的連線。 使用 顯示模式 控制項可傳回頁面以瀏覽模式。 接下來,按一下 [ 動態連線 ] 按鈕,以程式設計方式建立連線。 再次按一下 [ 連接點詳細資料] 按鈕,以指出兩個連接點物件的詳細資料。

備註

每個網頁元件連線都包含兩個伺服器控制項共用資料:一個控制項是取用者,另一個則是提供者。 如需網頁元件連線的基本元件和連線物件本身的討論,請參閱 WebPartConnection 類別概觀。 每個網頁元件連線都需要連接點。 提供者和取用者控制項必須至少有一個定義的 ConnectionPoint 物件, (每個物件都可以選擇性地有多個連接點) ,其中包含控制項如何連接到另一個控制項的詳細資料,以及它可以共用的資料類型。 在實際連接中,提供者有自己的連接點物件類型, (衍生自基 ConnectionPoint 類) 、 ProviderConnectionPoint 實例,而取用者有自己的物件,也就是 ConsumerConnectionPoint 實例。

若要建立提供者連接點,開發人員必須將回呼方法新增至提供者,以將實作的介面實例傳回給取用者。 它們必須使用程式碼 ConnectionProvider 屬性標記原始程式碼中的回呼方法, (查看 ConnectionProviderAttribute 類別) 。 同樣地,若要建立取用者連接點,開發人員必須將方法新增至接收介面實例的取用者,而且必須將該方法標示為 ConnectionConsumer 屬性, (查看 ConnectionConsumerAttribute 類別) 。

當開發人員在網頁上建立連線時,可以建立為靜態或動態連線。 靜態連線會在網頁的標記中宣告。 宣告靜態連接時,開發人員可以將值指派給 ProviderConnectionPointID 元素標記內的 <asp:webpartconnection>ConsumerConnectionPointID 屬性,以指定取用者和提供者所使用的連接點。 如果在取用者和提供者控制項內定義了多個連接點,此方法特別有用,因為它可讓靜態連接識別要用於連接的連接點。

動態連線是由開發人員的程式碼或使用者透過控制項所提供的 ConnectionsZone 使用者介面 (UI) ,以程式設計方式建立。 若要在程式碼中建立連接,開發人員必須在 控制項上 WebPartManager 呼叫 ConnectWebParts 方法,以取得 物件的實例 WebPartConnection 。 開發人員必須先參考取用者和提供者伺服器控制項及其各自的連接點物件,才能呼叫此方法。 若要取得提供者和取用者控制項之連接點的參考,開發人員會先在 控制項上 WebPartManager 呼叫 GetProviderConnectionPointsGetConsumerConnectionPoints 方法。 這些方法會傳回適當的連接點物件,接著可以傳遞至方法來建立連接。

當提供者和取用者的連接點物件都使用相同的介面類別型時,它們就相容,而且可以形成直接連線來共用資料。 如果它們無法與相同的介面類別型搭配使用, WebPartTransformer 則必須使用 物件,將介面實例從提供者轉譯為取用者可以使用的類型。

抽象 ConnectionPoint 類提供取用者和提供者控制項所共用之連接點的基底詳細資料。 數個屬性包含這些詳細資料。 屬性 AllowsMultipleConnections 會指出連接點是否可以一次參與一個以上的連接。 根據預設,提供者連接點可以參與多個連線,而取用者連接點則無法參與。 屬性 ControlType 表示與連接點相關聯的伺服器控制項類型。 請注意,不僅 WebPart 控制項可以形成連線;如果放置在 WebPartZoneBase 區域中,任何伺服器控制項,無論是 ASP.NET 控制項、自訂控制項或使用者控制項,都可以啟用參與連線。 屬性 DisplayName 會提供連接點的易記名稱,可在 UI 中顯示,以協助建立連線的使用者。 屬性 ID 可作為連接點物件本身的字串識別碼。 屬性 InterfaceType 會指出連接點所瞭解的介面實例類型。 指定的連接點是否提供或取用該介面的實例,取決於它是 ProviderConnectionPointConsumerConnectionPoint 物件。

類別 ConnectionPoint 有一個方法。 方法 GetEnabled 會傳回 Boolean 值,指出連接點目前是否能夠參與連線。

類別 ConnectionPoint 也有一個公用欄位: DefaultID 。 此欄位包含用來識別連接中預設連接點的值。

注意

指定連接點方法的屬性只有一個必要的參數, displayName 因此可以建立預設連接點屬性而不指定識別碼。 在這種情況下, DefaultID 欄位會提供要使用的基底值。

欄位

DefaultID

表示字串,用來識別與伺服器控制項關聯之連接點集合中的預設連接點。

屬性

AllowsMultipleConnections

取得值,指出連接點是否支援多個同時連接。

ControlType

取得與連接點關聯之伺服器控制項的 Type

DisplayName

取得字串,此字串在使用者介面 (UI) 做為表示連接點的易記顯示名稱。

ID

取得字串,其中包含連接點的識別項。

InterfaceType

取得連接點所使用的介面型別。

方法

Equals(Object)

判斷指定的物件是否等於目前的物件。

(繼承來源 Object)
GetEnabled(Control)

傳回值,指出連接點是否可以參與連接。

GetHashCode()

做為預設雜湊函式。

(繼承來源 Object)
GetType()

取得目前執行個體的 Type

(繼承來源 Object)
MemberwiseClone()

建立目前 Object 的淺層複製。

(繼承來源 Object)
ToString()

傳回代表目前物件的字串。

(繼承來源 Object)

適用於

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