DynamicFilter 类

定义

public ref class DynamicFilter : System::Web::UI::Control

public ref class DynamicFilter : System::Web::UI::Control, System::Web::DynamicData::IFilterExpressionProvider

public class DynamicFilter : System.Web.UI.Control

public class DynamicFilter : System.Web.UI.Control, System.Web.DynamicData.IFilterExpressionProvider

type DynamicFilter = class
    inherit Control

type DynamicFilter = class
    inherit Control
    interface IFilterExpressionProvider

Public Class DynamicFilter
Inherits Control

Public Class DynamicFilter
Inherits Control
Implements IFilterExpressionProvider

继承

Object

Control

DynamicFilter

实现

IFilterExpressionProvider

示例

可在以下位置获取包含源代码的 Visual Studio 项目： 下载。

以下示例使用默认的 ForeignKey.ascx 筛选器模板创建 UI，用于按 ProductCategory 外键列筛选 Products 表行。 当用户选择 ProductCategory 值时，仅显示包含该值的行。

该示例需要以下内容：

• 动态数据网站或动态数据 Web 应用程序。 这使你可以为数据库创建 AdventureWorksLTDataContext 数据上下文，并为表创建要访问的类。 有关详细信息，请参阅 Walkthrough: Creating a New Dynamic Data Web Site using Scaffolding。

<%@ Page Language="C#" MasterPageFile="~/Site.master" 
    CodeFile="DynamicFilter.aspx.cs" Inherits="ForeignKeyFilter" %>

<%@ Register src="~/DynamicData/Content/GridViewPager.ascx" tagname="GridViewPager" tagprefix="asp" %>

<asp:Content ID="headContent" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">

    <asp:DynamicDataManager ID="DynamicDataManager1" runat="server" AutoLoadForeignKeys="true" />

    <h2 class="DDSubHeader"><%= table.DisplayName%> ForeignKey filter</h2>

    <asp:UpdatePanel ID="UpdatePanel1" runat="server">
        <ContentTemplate>
            <asp:ValidationSummary ID="ValidationSummary1" runat="server" 
                EnableClientScript="true"
                HeaderText="List of validation errors" />
            <asp:DynamicValidator runat="server" ID="GridViewValidator" 
                ControlToValidate="GridView1" Display="None" />
            
            <!-- Show that the filter selection 
                is retained after a post-back -->
            <asp:Button ID="Button1" runat="server" Text="Cause Postback" />    
            <span></span>The filter selection is retained after a postback.</span> 
         
            <br />
            
            <!-- Set the DynamicFilter control attributes. --> 
            Select Category: <asp:DynamicFilter runat="server" ID="CategoryFilter" 
            DataField="ProductCategory" FilterUIHint="ForeignKey" 
            OnFilterChanged="OnFilterSelectedIndexChanged" /><br />

            <!-- Data-bound control that shows the filtered table rows. -->
            <asp:GridView ID="GridView1" runat="server" DataSourceID="GridDataSource" 
                EnablePersistedSelection="true" PageSize="5" 
                AllowPaging="True" AllowSorting="True" CssClass="DDGridView">
                <Columns>
                    <asp:TemplateField>
                        <ItemTemplate>
                            <asp:LinkButton ID="DeleteLinkButton" runat="server" CommandName="Delete"
                                CausesValidation="true" Text="Delete"
                                OnClientClick='return confirm("Are you sure you want to delete this item?");'
                            />
                        </ItemTemplate>
                    </asp:TemplateField>
                </Columns>

                <PagerStyle CssClass="footer"/>        
                <PagerTemplate>
                    <asp:GridViewPager runat="server" />
                </PagerTemplate>
                <EmptyDataTemplate>
                    There are currently no items in this table.
                </EmptyDataTemplate>
            </asp:GridView>
            
            <!-- The provider that connects to the database -->
            <asp:LinqDataSource ID="GridDataSource" runat="server" 
                EnableDelete="true" 
                ContextTypeName="AdventureWorksLTDataContext"
                TableName="Products">
            </asp:LinqDataSource>
            
            <!-- The control that handles the details for querying 
            the database, after a user's filtering action -->
            <asp:QueryExtender ID="QueryBlock1" TargetControlID="GridDataSource" 
                runat="server">
                <asp:DynamicFilterExpression ControlID="CategoryFilter" />
            </asp:QueryExtender>
            
        </ContentTemplate>
    </asp:UpdatePanel>
 
</asp:Content>

<%@ Page Language="VB" MasterPageFile="~/Site.master" 
AutoEventWireup="true" CodeFile="DynamicFilter.aspx.vb" 
Inherits="ForeignKeyFilter" %>

<%@ Register src="~/DynamicData/Content/GridViewPager.ascx" tagname="GridViewPager" tagprefix="asp" %>

<asp:Content ID="headContent" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">

    <asp:DynamicDataManager ID="DynamicDataManager1" runat="server" AutoLoadForeignKeys="true" />

    <h2 class="DDSubHeader"><%= table.DisplayName%> ForeignKey filter</h2>

    <asp:UpdatePanel ID="UpdatePanel1" runat="server">
        <ContentTemplate>
            <asp:ValidationSummary ID="ValidationSummary1" runat="server" 
                EnableClientScript="true"
                HeaderText="List of validation errors" />
            <asp:DynamicValidator runat="server" ID="GridViewValidator" 
                ControlToValidate="GridView1" Display="None" />
            
            <!-- Show that the filter selection 
                is retained after a post-back -->
            <asp:Button ID="Button1" runat="server" Text="Cause Postback" />    
            <span></span>The filter selection is retained after a postback.</span> 
         
            <br />
            
            <!-- Set the DynamicFilter control attributes. --> 
            Select Category: <asp:DynamicFilter runat="server" ID="CategoryFilter" 
            DataField="ProductCategory" FilterUIHint="ForeignKey" 
            OnFilterChanged="OnFilterSelectedIndexChanged" /><br />

            <!-- Data-bound control that shows the filtered table rows. -->
            <asp:GridView ID="GridView1" runat="server" DataSourceID="GridDataSource" 
                EnablePersistedSelection="true" PageSize="5" 
                AllowPaging="True" AllowSorting="True" CssClass="DDGridView">
                <Columns>
                    <asp:TemplateField>
                        <ItemTemplate>
                            <asp:LinkButton ID="DeleteLinkButton" runat="server" CommandName="Delete"
                                CausesValidation="true" Text="Delete"
                                OnClientClick='return confirm("Are you sure you want to delete this item?");'
                            />
                        </ItemTemplate>
                    </asp:TemplateField>
                </Columns>

                <PagerStyle CssClass="footer"/>        
                <PagerTemplate>
                    <asp:GridViewPager ID="GridViewPager1" runat="server" />
                </PagerTemplate>
                <EmptyDataTemplate>
                    There are currently no items in this table.
                </EmptyDataTemplate>
            </asp:GridView>
            
            <!-- The provider that connects to the database -->
            <asp:LinqDataSource ID="GridDataSource" runat="server" 
                EnableDelete="true" 
                ContextTypeName="AdventureWorksLTDataContext"
                TableName="Products">
            </asp:LinqDataSource>
            
            <!-- The control that handles the details for querying 
            the database, after a user's filtering action -->
            <asp:QueryExtender ID="QueryBlock1" TargetControlID="GridDataSource" 
                runat="server">
                <asp:DynamicFilterExpression ControlID="CategoryFilter" />
            </asp:QueryExtender>
            
        </ContentTemplate>
    </asp:UpdatePanel>
 
</asp:Content>

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml.Linq;
using System.Web.DynamicData;

    public partial class ForeignKeyFilter : System.Web.UI.Page {
        protected MetaTable table;

        protected void Page_Init(object sender, EventArgs e) {
            DynamicDataManager1.RegisterControl(GridView1, 
                true /* setSelectionFromUrl */);
        }

        protected void Page_Load(object sender, EventArgs e) {
            table = GridDataSource.GetTable();
            Title = table.DisplayName;

            // Disable various options if the table is readonly
            if (table.IsReadOnly) {
                GridView1.Columns[0].Visible = false;
            }
        }

        // Handle the filter change event.
        protected void OnFilterSelectedIndexChanged(object sender, EventArgs e) {
            // Reset the index of the page to display after 
            // the data filter value has been changed.
            GridView1.PageIndex = 0;
        }
    }

Imports System.Data
Imports System.Configuration
Imports System.Collections
Imports System.Linq
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls
Imports System.Xml.Linq
Imports System.Web.DynamicData


Partial Public Class ForeignKeyFilter
    Inherits System.Web.UI.Page
    Protected table As MetaTable

    Protected Sub Page_Init(ByVal sender As Object, ByVal e As EventArgs)
        'setSelectionFromUrl
        DynamicDataManager1.RegisterControl(GridView1, True)
    End Sub

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        table = GridDataSource.GetTable()
        Title = table.DisplayName

        ' Disable various options if the table is readonly
        If table.IsReadOnly Then
            GridView1.Columns(0).Visible = False
        End If
    End Sub

    ' Handle the filter change event.
    Protected Sub OnFilterSelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs)
        ' Reset the index of the page to display after 
        ' the data filter value has been changed.
        GridView1.PageIndex = 0

    End Sub

End Class

注解

本主题内容：

• 介绍

• ClassContext

• 声明性语法

介绍

控件 DynamicFilter 用于在页面标记中生成用于筛选表行的 UI。 动态数据使用 ~\DynamicData\Filters 文件夹中的默认筛选器模板创建 UI。 这些模板支持外键、布尔和枚举列类型。

下表显示了可以执行的一些任务。

可以通过以下方式指定要使用的筛选器模板：

• 通过在页面标记中使用 FilterUIHint 属性。 此方法是一种表示层自定义，它独立于数据库) (架构，适用于单个页面。

• 通过在模型中使用 FilterUIHintAttribute 特性。 此方法是一种数据层自定义，它依赖于数据库) (特定架构，适用于整个应用程序。

如果使用这两种方法，则标记中指定的筛选器模板优先于数据模型中指定的模板。

类上下文

控件 DynamicFilter 旨在与 控件配合使用 QueryExtender 。 控件 DynamicFilter 由 DynamicFilterExpression 页面标记中的 对象内的 QueryExtender 实例引用。

下图显示了动态数据为通过外键列实现表行筛选所遵循的步骤。

1. 控件 DynamicFilter 将所选值传递给 控件 QueryExtender 。

2. 控件 QueryExtender 使用 值创建查询筛选信息。 然后，它将此信息传递给数据源控件。

3. 数据源控件将筛选查询信息传递给数据源提供程序。

4. 数据源提供程序将查询传递到数据库。

5. 数据库返回筛选的表行。

6. 数据源提供程序将此数据发送回数据源控件。

7. 数据源控件将筛选的表行传递给数据绑定控件以供显示。

声明性语法

<asp:DynamicFilter  
    ID="Control ID"  
    DataField="Name of the data field to use for filtering"  
    EnableViewState="True|False"   
    FilterUIHint="Name of the filter template to generate the UI"  
    OnFilterChanged="Filter changed event handler"  
    OnDataBinding="DataBinding event handler"  
    OnDisposed="Disposed event handler"  
    OnInit="Init event handler"  
    OnLoad="Load event handler"  
    OnPreRender="PreRender event handler"  
    OnUnload="Unload event handler"   
    Visible="True|False"  
    runat="server"/>  

构造函数

属性

方法

事件

显式接口实现

扩展方法

适用于

另请参阅

• QueryableFilterRepeater
• 演练：筛选具有Parent-Child关系的表中的行