@ Implements

更新:2007 年 11 月

指示当前的 ASP.NET 应用程序文件(网页、用户控件或母版页)实现指定的 .NET Framework 接口。

<%@ Implements interface="ValidInterfaceName" %>

属性

  • interface
    要在页或用户控件中实现的接口。

备注

当在 Web 窗体页中实现接口时,您可以在代码声明块中 <script> 元素的开始标记和结束标记之间创建其事件、方法和属性。您不能使用该指令在代码隐藏文件中实现接口。

示例

下面的代码示例演示了一个用户控件,它包含一个用于访问 IWebPart 接口的六个属性的 @ Implements 指令。在用户控件中实现这些属性后,当您将用户控件放置在 WebPartZone 控件内部时,它能够具有 WebPart 控件的属性和外观。代码示例的第一部分是用户控件;将这段代码放置在一个文件中,并将文件命名为 CalendarUserControl.ascx。

代码示例的第二部分是用户控件的宿主页。注意,该页使用 @ Register 指令来注册用户控件,以便在该页上使用。另请注意,当用户控件在页的正文中声明时,使用声明性语法为某些 IWebPart 属性(如 TitleDescription)分配值。有关如何将用户控件包含在 Web 窗体页中的更多信息,请参见 @ Register自定义服务器控件语法如何:在 ASP.NET 网页中包括用户控件。有关 Web 部件页的信息,请参见 ASP.NET Web 部件控件

<!-- A user control that implements an interface. -->
<%@ Control language="C#" ClassName="CalendarUserControl" %>
<%@ implements 
    interface="System.Web.UI.WebControls.WebParts.IWebPart" %>

<script runat="server">

  private string m_Description;
  private string m_Title;
  private string m_TitleIconImageUrl;
  private string m_TitleUrl;
  private string m_CatalogIconImageUrl;
  
  [Personalizable]
  public string Description
  {
    get
    {
      object objTitle = ViewState["Description"];
      if (objTitle == null)
        return String.Empty;

      return (string)objTitle;
    }
    set
    {
      ViewState["Description"] = Server.HtmlEncode(value);
    }
  }

  [Personalizable]
  public string Title
  {
    get
    {
      object objTitle = ViewState["Title"];
      if (objTitle == null)
        return String.Empty;

      return (string)objTitle;
    }
    set
    {
      ViewState["Title"] = Server.HtmlEncode(value);
    }
  }

  public string Subtitle
  {
    get
    {
      object objSubTitle = ViewState["Subtitle"];
      if (objSubTitle == null)
        return "Acme Corp";
      return (string)objSubTitle;
    }

  }

  [Personalizable]
  public string TitleIconImageUrl
  {
    get
    {
      object objTitle = ViewState["TitleIconImageUrl"];
      if (objTitle == null)
        return String.Empty;

      return (string)objTitle;
    }
    set
    {
      ViewState["TitleIconImageUrl"] = Server.HtmlEncode(value);
    }
  }

  [Personalizable]
  public string TitleUrl
  {
    get
    {
      object objTitle = ViewState["TitleUrl"];
      if (objTitle == null)
        return String.Empty;

      return (string)objTitle;
    }
    set
    {
      ViewState["TitleUrl"] = Server.HtmlEncode(value);
    }
  }

  [Personalizable]
  public string CatalogIconImageUrl
  {
    get
    {
      object objTitle = ViewState["CatalogIconImageUrl"];
      if (objTitle == null)
        return String.Empty;

      return (string)objTitle;
    }
    set
    {
      ViewState["CatalogIconImageUrl"] = Server.HtmlEncode(value);
    }
  }

</script>
<asp:calendar id="Calendar1" runat="server" />


<!-- A page that registers and hosts the user control. -->
<%@ Page language="C#" %>
<%@ register tagprefix="uc1" 
    tagname="CalControl" 
    src="~/CalendarUserControl.ascx" %>

<!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>Calendar Page</title>
</head>
<body>
  <form id="form1" runat="server">
    <asp:webpartmanager id="manager1" runat="server" />
    <asp:webpartzone id="WebPartZone1" runat="server">
      <zonetemplate>
        <uc1:CalControl id="CalControl1" runat="server" 
          title="Personal Calendar" 
          description="My personal calendar for work." />      
      </zonetemplate>
    </asp:webpartzone>
  </form>
</body>
</html>
<!-- A user control that implements an interface. -->
<%@ Control language="VB" ClassName="CalendarUserControl" %>
<%@ implements 
    interface="System.Web.UI.WebControls.WebParts.IWebPart" %>

<script runat="server">

  Private m_Description As String
  Private m_Title As String
  Private m_TitleIconImageUrl As String
  Private m_TitleUrl As String
  Private m_CatalogIconImageUrl As String
  
  <Personalizable()> _
  Public Property Description() As String _
    Implements IWebPart.Description
    Get
      Dim objTitle As Object = ViewState("Description")
      If objTitle Is Nothing Then
        Return String.Empty
      End If
      Return CStr(objTitle)
    End Get
    Set(ByVal value As String)
      ViewState("Description") = Server.HtmlEncode(value)
    End Set
  End Property

  <Personalizable()> _
  Public Property Title() As String _
    Implements IWebPart.Title
    Get
      Dim objTitle As Object = ViewState("Title")
      If objTitle Is Nothing Then
        Return String.Empty
      End If
      Return CStr(objTitle)
    End Get
    Set(ByVal value As String)
      ViewState("Title") = Server.HtmlEncode(value)
    End Set
  End Property

  ReadOnly Property Subtitle() As String _
    Implements IWebPart.Subtitle
    Get
      Dim objSubTitle As Object = ViewState("Subtitle")
      If objSubTitle Is Nothing Then
        Return "Acme Corp"
      End If
      Return CStr(objSubTitle)
    End Get
  End Property

  <Personalizable()> _
  Public Property TitleIconImageUrl() As String _
    Implements IWebPart.TitleIconImageUrl
    Get
      Dim objTitle As Object = ViewState("TitleIconImageUrl")
      If objTitle Is Nothing Then
        Return String.Empty
      End If
      Return CStr(objTitle)
    End Get
    Set(ByVal value As String)
      ViewState("TitleIconImageUrl") = Server.HtmlEncode(value)
    End Set
  End Property

  <Personalizable()> _
  Public Property TitleUrl() As String _
    Implements IWebPart.TitleUrl
    Get
      Dim objTitle As Object = ViewState("TitleUrl")
      If objTitle Is Nothing Then
        Return String.Empty
      End If
      Return CStr(objTitle)
    End Get
    Set(ByVal value As String)
      ViewState("TitleUrl") = Server.HtmlEncode(value)
    End Set
  End Property

  <Personalizable()> _
  Public Property CatalogIconImageUrl() As String _
    Implements IWebPart.CatalogIconImageUrl
    Get
      Dim objTitle As Object = ViewState("CatalogIconImageUrl")
      If objTitle Is Nothing Then
        Return String.Empty
      End If
      Return CStr(objTitle)
    End Get
    Set(ByVal value As String)
      ViewState("CatalogIconImageUrl") = Server.HtmlEncode(value)
    End Set
  End Property

</script>
<asp:calendar id="Calendar1" runat="server" />


<!-- A page that registers and hosts the user control. -->
<%@ Page language="VB" %>
<%@ register tagprefix="uc1" 
    tagname="CalControl" 
    src="~/CalendarUserControl.ascx" %>

<!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>Calendar Page</title>
</head>
<body>
  <form id="form1" runat="server">
    <asp:webpartmanager id="manager1" runat="server" />
    <asp:webpartzone id="WebPartZone1" runat="server">
      <zonetemplate>
        <uc1:CalControl id="CalControl1" runat="server" 
          title="Personal Calendar" 
          description="My personal calendar for work." />      
      </zonetemplate>
    </asp:webpartzone>
  </form>
</body>
</html>

请参见

任务

如何:在 ASP.NET 网页中包括用户控件

概念

ASP.NET 网页语法概述

ASP.NET 网页代码模型

参考

指令语法

其他资源

ASP.NET Web 部件控件