WebPartManager.ConnectDisplayMode 字段 (System.Web.UI.WebControls.WebParts)

.NET Framework 类库

WebPartManager.ConnectDisplayMode 字段

注意：此字段在 .NET Framework 2.0 版中是新增的。

表示用于显示特殊用户界面 (UI) 以便用户管理 WebPart 控件之间的连接的显示模式。此字段为只读。

命名空间:System.Web.UI.WebControls.WebParts
程序集:System.Web（在 system.web.dll 中）

语法

Visual Basic（声明）

Public Shared ReadOnly ConnectDisplayMode As WebPartDisplayMode

Visual Basic（用法）

Dim value As WebPartDisplayMode

value = WebPartManager.ConnectDisplayMode

public static readonly WebPartDisplayMode ConnectDisplayMode

C++

public:
static initonly WebPartDisplayMode^ ConnectDisplayMode

public static final WebPartDisplayMode ConnectDisplayMode

JScript

public static final var ConnectDisplayMode : WebPartDisplayMode

备注

ConnectDisplayMode 字段引用一个自定义 WebPartDisplayMode 对象，该对象由 WebPartManager 控件创建，并包含在该控件中。因为这是一个静态对象，所以可以通过 WebPartManager 类直接引用它，而无需该控件的实例。

用户要管理某一网页上 WebPart 控件之间的连接时，如果已在该页上声明了一个 ConnectionsZone 区域，则可将该页切换至 ConnectDisplayMode 模式。连接显示模式显示一个用于管理连接的特殊用户界面，该界面可用来连接控件或断开控件连接，以及编辑现有连接的详细信息。

如果要使用户能够使用由 Web 部件控件集提供的用户界面管理连接，必须在页标记中声明一个 <asp:connectionszone> 元素。与其他类型的 WebZone 区域的元素不同，您不必在此元素内添加任何其他标记；您只需声明该元素本身。

示例

下面的代码示例演示 ConnectDisplayMode 模式的用法。

该代码示例包括三部分：

一个源文件，其中包含一个接口以及能够形成连接的若干自定义 WebPart 控件。
一个网页，该网页提供一个连接用户界面并演示如何使用 ConnectDisplayMode 模式。
关于如何运行该示例的说明。

该代码示例的第一部分是一个源文件，其中包含一个接口和两个设计为可以连接的自定义 WebPart 控件。必须编译此源代码，代码示例才能运行。可以显式编译源代码，并将结果程序集放在网站的 Bin 文件夹或全局程序集缓存中。另外，也可将源代码放入站点的 App_Code 文件夹中，源代码将在运行时在此文件夹中进行动态编译。此代码示例使用动态编译方法。有关演示如何编译的演练，请参见演练：开发和使用自定义服务器控件。

Visual Basic

Imports System
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", "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", "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 'OnPreRender

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

    End Sub

  End Class

End Namespace

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", "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 (input.Text != String.Empty)
      {
        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", "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);
    }

  }
}

该示例的第二部分是一个包含自定义控件的网页。在页上的服务器 <script> 标记内有几个方法，这些方法使用页上可用的显示模式填充一个下拉列表。用户可从该下拉列表进行选择来更改页的显示模式。由于在页的标记中声明了一个 <asp:connectionszone> 元素，所以连接显示模式是可用的显示模式之一。注意，此元素不包含任何其他子元素；其存在只是为了使用户能够使用连接管理用户界面。

在此示例中，ConnectDisplayMode 模式在两个位置出现。第一个位置在 Page_Init 方法中，连接显示模式在代码依次通过 SupportedDisplayModes 属性中引用的集合时添加到显示模式下拉列表中。第二个位置，Page_PreRender 方法检查页上的当前显示模式，如果当前模式是 ConnectDisplayMode，则在 Label 控件中显示一条消息。

Visual Basic

<%@ Page Language="vb" %>
<%@ Register TagPrefix="aspSample" 
    Namespace="Samples.AspNet.VB.Controls" %>

<script runat="server">
  
  Protected Sub Page_Init(ByVal sender As Object, _
    ByVal e As EventArgs)
    
    Dim mode As WebPartDisplayMode
    For Each mode In mgr.SupportedDisplayModes
      Dim modeName As String = mode.Name
      If mode.IsEnabled(mgr) Then
        Dim item As ListItem = New ListItem(modeName, modeName)
        DisplayModeDropdown.Items.Add(item)
      End If
    Next
    
  End Sub

  Protected Sub DisplayModeDropdown_SelectedIndexChanged(ByVal _
    sender As Object, ByVal e As EventArgs)
    
    Dim selectedMode As String = _
      DisplayModeDropdown.SelectedValue
    Dim mode As WebPartDisplayMode = _
      mgr.SupportedDisplayModes(selectedMode)
    If mode IsNot Nothing Then
      mgr.DisplayMode = mode
    End If
    
  End Sub
  
  Protected Sub Page_PreRender(ByVal sender As Object, _
    ByVal e As System.EventArgs)
    If mgr.DisplayMode.Equals(WebPartManager.ConnectDisplayMode) Then
      Label1.Visible = True
    Else
      Label1.Visible = False
    End If
  End Sub
  
</script>

<html  >
<head id="Head1" runat="server">
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:WebPartManager ID="mgr" runat="server" />    
      <asp:Label ID="Label1" runat="server" 
        Text="Currently in Connect Display Mode" 
        Font-Bold="true"
        Font-Size="125%" />
      <br />
      <asp:DropDownList ID="DisplayModeDropdown" 
        runat="server" 
        AutoPostBack="true"
        Width="120"
        OnSelectedIndexChanged=
        "DisplayModeDropdown_SelectedIndexChanged">
      </asp:DropDownList>
      <hr />
      <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" />
    </div>
    </form>
</body>
</html>

<%@ Page Language="C#" %>
<%@ Register TagPrefix="aspSample" 
    Namespace="Samples.AspNet.CS.Controls" %>

<script runat="server">

  protected void Page_Init(object sender, EventArgs e)
  {
    foreach (WebPartDisplayMode mode in mgr.SupportedDisplayModes)
    {
      string modeName = mode.Name;
      if (mode.IsEnabled(mgr))
      {
        ListItem item = new ListItem(modeName, modeName);
        DisplayModeDropdown.Items.Add(item);
      }      
    }
  }

  protected void DisplayModeDropdown_SelectedIndexChanged(object 
    sender, EventArgs e)
  {
    String selectedMode = DisplayModeDropdown.SelectedValue;
    WebPartDisplayMode mode = 
      mgr.SupportedDisplayModes[selectedMode];
    if (mode != null)
      mgr.DisplayMode = mode;
  }

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

<html  >
<head runat="server">
</head>
<body>
    <form id="form1" runat="server">
    <div>
      <asp:WebPartManager ID="mgr" runat="server" />    
      <asp:Label ID="Label1" runat="server" 
        Text="Currently in Connect Display Mode" 
        Font-Bold="true"
        Font-Size="125%" />
      <br />
      <asp:DropDownList ID="DisplayModeDropdown" 
        runat="server" 
        AutoPostBack="true"
        Width="120"
        OnSelectedIndexChanged=
        "DisplayModeDropdown_SelectedIndexChanged">
      </asp:DropDownList>
      <hr />
      <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" />
    </div>
    </form>
</body>
</html>

将该页加载到浏览器中之后，单击该下拉列表并选择“连接”，将该页切换至连接显示模式。注意，会显示一条消息，通知您该页处于连接显示模式。现在单击 WebPart 控件之一的标题栏中的谓词菜单（一个箭头符号），然后单击谓词菜单中的“连接”。显示连接用户界面之后，单击链接创建一个连接。使用显示的连接用户界面中的下拉列表选择将参与连接的另一控件，然后单击“连接”按钮。随即建立连接。单击“关闭”按钮，然后使用页顶部的下拉列表将该页返回浏览显示模式。

平台

Windows 98、Windows 2000 SP4、Windows Millennium Edition、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0

请参见

参考

WebPartManager 类
WebPartManager 成员
System.Web.UI.WebControls.WebParts 命名空间
DisplayModes
WebPartDisplayMode 类

其他资源

ASP.NET Web 部件页
Web 部件页显示模式