稳扎稳打Silverlight(57) 4.0通信之WCF RIA Services: 概述, 通过 DomainDataSource 实现数据的添加、查询、更新和删除操作

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稳扎稳打Silverlight(57) - 4.0通信之WCF RIA Services: 概述, 通过 DomainDataSource 实现数据的添加、查询、更新和删除操作

作者：webabcd


介绍
Silverlight 4.0 之 WCF RIA Services：概述以及如何通过 DomainDataSource 实现数据的添加、查询、更新和删除操作，以及服务端的查询、排序和分页等逻辑


在线DEMO
http://www.cnblogs.com/webabcd/archive/2010/08/09/1795417.html


示例
1、概述
Summary.xaml

<navigation:Page x:Class="Silverlight40.WCFRIAServices.Summary" 
           xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
           xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
           xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
           xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
           Title="Summary Page">
    <Grid x:Name="LayoutRoot">
        <StackPanel HorizontalAlignment="Left">
            
            <StackPanel Orientation="Horizontal">
                <Image Source="/WCFRIAServices/1.png" Margin="10" />
                <Image Source="/WCFRIAServices/2.png" Margin="10" />
                <Image Source="/WCFRIAServices/3.png" Margin="10" />
            </StackPanel>
            
            <TextBlock>
                <Run>1、WCF RIA Services link - 用于连接中间层和表现层，在 Silverlight 项目的属性中可以设置 WCF RIA Services link</Run>
                <LineBreak />
                <Run>2、图1：最简单的 WCF RIA Services link；图2：带有类库的 WCF RIA Services link；图3：带有多个 RIA Services 类库的 WCF RIA Services link</Run>
                <LineBreak />
                <Run>3、在服务端创建 Domain Service Class 用于提供服务，客户端的 Generated_Code 文件夹内会自动生成数据上下文代码</Run>
                <LineBreak />
                <Run>4、共享代码：中间层按 *.shared.cs 规范保存的代码会 push 到表现层的 Generated_Code 文件夹内；文件链接：添加已存在文件时，选择“Add As Link”，此为 pull 模型</Run>
            </TextBlock>
            
        </StackPanel>
    </Grid>
</navigation:Page>

2、演示 DomainDataSource 的应用
服务端：
MyDomainService.cs

/*
 * 一个 Domain Service 服务
 */

namespace Silverlight40.Web.Service
{
    using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.ComponentModel.DataAnnotations;
    using System.Data;
    using System.Linq;
    using System.ServiceModel.DomainServices.EntityFramework;
    using System.ServiceModel.DomainServices.Hosting;
    using System.ServiceModel.DomainServices.Server;
    using Silverlight40.Web.Model;

    /*
     * 用 LinqToEntities 实现 Domain Service 则继承 LinqToSqlDomainService<NorthwindEntities>；用 LinqToSql 实现 Domain Service 则继承 LinqToSqlDomainService<NorthwindEntities>
     * Domain Service 内所有对客户端可见的方法都应该是 public 的，Domain Service 内的方法不支持重载
     * 对客户端可见的方法要满足命名约定，或为其指定对应的 Attribute。当前支持 6 种数据操作：Query, Update, Insert, Delete, Invoke, Named Update, 详见文档
     * 
     * [EnableClientAccess()] - 该类对客户端可见
     * [EnableClientAccess(RequiresSecureEndpoint = true)] - 使用 HTTPS 协议
     * [Ignore] - 指定的方法不作为服务而公开
     * [Query(IsComposable=true)] - 支持客户端的 linq 查询，而且此查询会被在服务端执行
     * 
     * 在多个 Domain Services 间共享实体：通过 [ExternalReference], [Association()], Context.AddReference() 实现，详见文档
     */

    // 服务端的类名为：MyDomainService，则其生成的客户端上下文的类名为：MyDomainContext
    [EnableClientAccess()]
    public class MyDomainService : LinqToEntitiesDomainService<NorthwindEntities>
    {
        [Query(IsDefault = true)]
        public IQueryable<Category> GetCategories()
        {
            return this.ObjectContext.Categories;
        }

        public void InsertCategory(Category category)
        {
            if ((category.EntityState != EntityState.Detached))
            {
                this.ObjectContext.ObjectStateManager.ChangeObjectState(category, EntityState.Added);
            }
            else
            {
                this.ObjectContext.Categories.AddObject(category);
            }
        }

        public void UpdateCategory(Category currentCategory)
        {
            this.ObjectContext.Categories.AttachAsModified(currentCategory, this.ChangeSet.GetOriginal(currentCategory));
        }

        public void DeleteCategory(Category category)
        {
            if ((category.EntityState == EntityState.Detached))
            {
                this.ObjectContext.Categories.Attach(category);
            }
            this.ObjectContext.Categories.DeleteObject(category);
        }



        [Query(IsDefault = true)]
        public IQueryable<Product> GetProducts()
        {
            return this.ObjectContext.Products;
        }

        public IQueryable<Product> GetProductsBySort(string sort)
        {
            return ObjectContext.Products.OrderBy(sort);
        }

        public void InsertProduct(Product product)
        {
            if ((product.EntityState != EntityState.Detached))
            {
                this.ObjectContext.ObjectStateManager.ChangeObjectState(product, EntityState.Added);
            }
            else
            {
                this.ObjectContext.Products.AddObject(product);
            }
        }

        public void UpdateProduct(Product currentProduct)
        {
            this.ObjectContext.Products.AttachAsModified(currentProduct, this.ChangeSet.GetOriginal(currentProduct));
        }

        public void DeleteProduct(Product product)
        {
            if ((product.EntityState == EntityState.Detached))
            {
                this.ObjectContext.Products.Attach(product);
            }
            this.ObjectContext.Products.DeleteObject(product);
        }

        public IQueryable<Product> GetProductsByCategoryId(int categoryId)
        {
            return this.ObjectContext.Products.Where(p => p.CategoryID == categoryId);
        }
    }
}

MyDomainService.metadata.cs

/*
 * [MetadataTypeAttribute()] - 指定类的元数据对象
 * [Include] - 生成的客户端上下文包含此字段
 * [Exclude] - 生成的客户端上下文不包含此字段
 * [Composition] - 指定字段为关联数据，即父实体增删改查时，此关联数据也会做相应的变化。指定此 Attribute 后，需显式指定其为 [Include]
 * [Editable(true)], [Editable(false)] - 指定字段是否可编辑
 */

namespace Silverlight40.Web.Model
{
    using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.ComponentModel.DataAnnotations;
    using System.Data.Objects.DataClasses;
    using System.Linq;
    using System.ServiceModel.DomainServices.Hosting;
    using System.ServiceModel.DomainServices.Server;

    [MetadataTypeAttribute(typeof(Category.CategoryMetadata))]
    public partial class Category
    {
        internal sealed class CategoryMetadata
        {
            private CategoryMetadata()
            {
            }

            [Key()]
            public int CategoryID { get; set; }

            [Display(Name = "类别名称")] // 显示用
            public string CategoryName { get; set; }

            public string Description { get; set; }

            [Exclude]
            public byte[] Picture { get; set; }

            [Include]
            // [Composition]
            public EntityCollection<Product> Products { get; set; }
        }
    }

    [MetadataTypeAttribute(typeof(Product.ProductMetadata))]
    public partial class Product
    {
        internal sealed class ProductMetadata
        {
            private ProductMetadata()
            {
            }

            public Category Category { get; set; }

            public Nullable<int> CategoryID { get; set; }

            public bool Discontinued { get; set; }

            public EntityCollection<Order_Detail> Order_Details { get; set; }

            [Display(Order = 0, Name = "产品ID")]
            public int ProductID { get; set; }

            [Display(Order = 1, Name = "产品名称")]
            public string ProductName { get; set; }

            public string QuantityPerUnit { get; set; }

            public Nullable<short> ReorderLevel { get; set; }

            public Supplier Supplier { get; set; }

            public Nullable<int> SupplierID { get; set; }

            public Nullable<decimal> UnitPrice { get; set; }

            public Nullable<short> UnitsInStock { get; set; }

            public Nullable<short> UnitsOnOrder { get; set; }
        }
    }
}

客户端：
DomainDataSourceDemo.xaml

<!--
    System.Windows.Controls.DomainServices 程序集的默认位置：
    C:\Program Files\Microsoft SDKs\RIA Services\v1.0\Libraries\Silverlight\System.Windows.Controls.DomainServices.dll
-->
<navigation:Page x:Class="Silverlight40.WCFRIAServices.DomainDataSourceDemo" 
           xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
           xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
           xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
           xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
           xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
           xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk"
           xmlns:riaControls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.DomainServices" 
           xmlns:my="clr-namespace:Silverlight40.Web.Service"
           Title="DomainDataSourceDemo Page">
    <Grid x:Name="LayoutRoot">
        <StackPanel HorizontalAlignment="Left">

            <!--
                用于演示添加记录
            -->
            <StackPanel Orientation="Horizontal">
                <sdk:Label Name="lblProductName4Add" Content="产品名称（添加用）:" />
                <TextBox Name="txtProductName4Add" Width="100" />
                <Button Name="btnAdd" Content="新增" Click="btnAdd_Click" />
            </StackPanel>

            <!--
                用于演示查询记录
            -->
            <StackPanel Orientation="Horizontal">
                <sdk:Label Name="lblProductName" Content="产品名称（查询用）:" />
                <TextBox Name="txtProductName" Width="100" />
            </StackPanel>

            <!--
                用于演示显示记录，更新记录，删除记录
                将 DataGrid 的数据源绑定到 DomainDataSource 对象上，相关的查询排序等逻辑在 DomainDataSource 对象内设置
            -->
            <sdk:DataGrid Name="dataGrid" Width="600" Height="300" AutoGenerateColumns="False" ItemsSource="{Binding ElementName=productDomainDataSource, Path=Data}">
                <sdk:DataGrid.Columns>
                    <sdk:DataGridTextColumn Header="供应商ID" Binding="{Binding SupplierID}" IsReadOnly="True" />
                    <sdk:DataGridTextColumn Header="产品类别ID" Binding="{Binding CategoryID}" IsReadOnly="True" />
                    <sdk:DataGridTextColumn Header="产品ID" Binding="{Binding ProductID}" IsReadOnly="True" />
                    <sdk:DataGridTextColumn Header="产品名称" Binding="{Binding ProductName}" />
                    <sdk:DataGridTemplateColumn Header="删除">
                        <sdk:DataGridTemplateColumn.CellTemplate>
                            <DataTemplate>
                                <Grid>
                                    <Button Name="btnDelete" Content="删除" Click="btnDelete_Click" />
                                </Grid>
                            </DataTemplate>
                        </sdk:DataGridTemplateColumn.CellTemplate>
                    </sdk:DataGridTemplateColumn>
                </sdk:DataGrid.Columns>
            </sdk:DataGrid>
            
            <!--
                将 DataPager 的数据源绑定到 DomainDataSource 对象上，即可实现服务端分页
            -->
            <sdk:DataPager Name="dataPager" Width="600" Height="30" PageSize="5" Source="{Binding ElementName=productDomainDataSource, Path=Data}" />
            
            <Button Name="btnSave" Content="保存" Click="btnSave_Click" />
            
        </StackPanel>

        <!--
            DomainDataSource - 一种数据源控件，通过一个 Domain 上下文关联 UI 和 WCF RIA Services。其所有查询操作均在服务端完成
                QueryName - 指定查询方法
                AutoLoad - 是否自动加载数据
                FilterOperator - 各个 FilterDescriptor 间的逻辑关系。“And”或“Or”
        -->
        <riaControls:DomainDataSource Name="productDomainDataSource" QueryName="GetProductsByCategoryIdQuery" AutoLoad="True" FilterOperator="Or">

            <!--
                指定数据上下文，来自 Silverlight40.Web.Service.MyDomainContext
            -->
            <riaControls:DomainDataSource.DomainContext>
                <my:MyDomainContext />
            </riaControls:DomainDataSource.DomainContext>

            <!--
                指定查询参数，为 GetProductsByCategoryId 方法传递参数，参数名：categoryId，参数值：1
            -->
            <riaControls:DomainDataSource.QueryParameters>
                <riaControls:Parameter ParameterName="categoryId" Value="1" />
            </riaControls:DomainDataSource.QueryParameters>

            <!--
                指定排序逻辑，按 SupplierID 字段正序排序
            -->
            <riaControls:DomainDataSource.SortDescriptors>
                <riaControls:SortDescriptor Direction="Ascending" PropertyPath="SupplierID" />
            </riaControls:DomainDataSource.SortDescriptors>

            <!--
                指定分组逻辑，按 SupplierID 字段分组显示
            -->
            <riaControls:DomainDataSource.GroupDescriptors>
                <riaControls:GroupDescriptor PropertyPath="SupplierID" />
            </riaControls:DomainDataSource.GroupDescriptors>

            <!--
                指定过滤逻辑，筛选逻辑为：ProductName 字段数据包含“a”或者 ProductName 字段数据包含 txtProductName.Text 中的内容
            -->
            <riaControls:DomainDataSource.FilterDescriptors>
                <riaControls:FilterDescriptor Operator="Contains" PropertyPath="ProductName" Value="a" />
                <riaControls:FilterDescriptor Operator="Contains" PropertyPath="ProductName" Value="{Binding ElementName=txtProductName, Path=Text}" />
            </riaControls:DomainDataSource.FilterDescriptors>

        </riaControls:DomainDataSource>
    </Grid>
</navigation:Page>

DomainDataSourceDemo.xaml.cs

/*
 * 演示通过 DomainDataSource 实现数据的添加、查询、更新和删除操作，以及服务端的查询、排序和分页等逻辑 
 */

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Navigation;

using Silverlight40.Web.Model;
using System.ServiceModel.DomainServices.Client;

namespace Silverlight40.WCFRIAServices
{
    public partial class DomainDataSourceDemo : Page
    {
        public DomainDataSourceDemo()
        {
            InitializeComponent();
        }

        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            // DomainDataSource.SubmitChanges() - 提交数据的变化
            // DomainDataSource.SubmittingChanges - SubmitChanges() 执行前所触发的事件
            // DomainDataSource.SubmittedChanges - SubmitChanges() 执行后所触发的事件
            // DomainDataSource.Load() - 加载查询结果

            productDomainDataSource.SubmittingChanges += new EventHandler<SubmittingChangesEventArgs>(productDomainDataSource_SubmittingChanges);
            productDomainDataSource.SubmittedChanges += new EventHandler<SubmittedChangesEventArgs>(productDomainDataSource_SubmittedChanges);
        }

        private void productDomainDataSource_LoadedData(object sender, LoadedDataEventArgs e)
        {
            if (e.HasError)
            {
                System.Windows.MessageBox.Show(e.Error.ToString(), "Load Error", System.Windows.MessageBoxButton.OK);
                e.MarkErrorAsHandled();
            }
        }

        private void btnSave_Click(object sender, RoutedEventArgs e)
        {
            productDomainDataSource.SubmitChanges();
        }

        void productDomainDataSource_SubmittingChanges(object sender, SubmittingChangesEventArgs e)
        {
            MessageBox.Show("Submitting");
        }

        void productDomainDataSource_SubmittedChanges(object sender, SubmittedChangesEventArgs e)
        {
            if (e.HasError)
            {
                MessageBox.Show(e.Error.ToString());
            }
            else
            {
                MessageBox.Show("Submitted");
                productDomainDataSource.Load();
            }
        }

        private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
            // DomainDataSource.DomainContext - 数据上下文对象 [System.ServiceModel.DomainServices.Client.DomainContext 类型]
            // DomainContext.EntityContainer - 数据上下文对象中的全部实体 [System.ServiceModel.DomainServices.Client.EntityContainer 类型]
            // EntityContainer.GetEntitySet<T>() - 获取指定类型的实体数据

            EntitySet<Product> products = productDomainDataSource.DomainContext.EntityContainer.GetEntitySet<Product>();
            Product product = new Product();
            product.ProductName = txtProductName4Add.Text;
            product.CategoryID = 1;
            product.SupplierID = 1;
            products.Add(product);

            productDomainDataSource.SubmitChanges();
        }

        private void btnDelete_Click(object sender, RoutedEventArgs e)
        {
            EntitySet<Product> products = productDomainDataSource.DomainContext.EntityContainer.GetEntitySet<Product>();
            Product product = dataGrid.SelectedItem as Product;
            products.Remove(product);

            productDomainDataSource.SubmitChanges();
        }
    }
}

OK
[源码下载]