WCF RIA Services 快速上手

WCF RIA Services 简化开发RIA n-tier 解决方案。让你快速构建Silverlight n-tier应用程序客户端与服务端的通信。下面我们来看一张图：

下面我们来构建一个简单的DEMO:

首先，下载Silverlight 4 Tools for Visual Studio 2010 ,建一个Silverlight project:

接下弹出对话框，记得Enable WCF RIA Services:

建立DEMO的表，并插入几条数据：

   1:  CREATE TABLE [dbo].[tblItem](

   2:      [ItemNumber] INT NOT NULL,

   3:      [ItemDescription] [varchar](50) NULL,

   4:      [Quantity] [int] NULL

   5:  CONSTRAINT [PK_tblItem] PRIMARY KEY CLUSTERED

   6:  (

   7:      [ItemNumber] ASC )

   8:  )

9:

  10:  INSERT INTO [tblItem]

  11:             ([ItemNumber]

  12:             ,[ItemDescription]

  13:             ,[Quantity])

  14:  VALUES ('1','Item Name1',1),

  15:         ('2','Item Name2',2),

  16:         ('3','Item Name3',3),

  17:         ('4','Item Name4',4),

  18:         ('5','Item Name5',5),

  19:         ('6','Item Name6',6)

接着我们对这个TABLE建EF4 DATA MODEL，这里我们将不再深入，待建立好后，创建DomainService:

然后选择那个Entities:

接下将会生成一个Service的文件：

   1:  namespace RIAServices.Web

   2:  {

   3:      using System;

   4:      using System.Collections.Generic;

   5:      using System.ComponentModel;

   6:      using System.ComponentModel.DataAnnotations;

   7:      using System.Data;

   8:      using System.Linq;

   9:      using System.ServiceModel.DomainServices.EntityFramework;

  10:      using System.ServiceModel.DomainServices.Hosting;

  11:      using System.ServiceModel.DomainServices.Server;

12:

13:

  14:      // Implements application logic using the BirdLLEntities context.

  15:      // TODO: Add your application logic to these methods or in additional methods.

  16:      // TODO: Wire up authentication (Windows/ASP.NET Forms) and uncomment the following to disable anonymous access

  17:      // Also consider adding roles to restrict access as appropriate.

  18:      // [RequiresAuthentication]

  19:      [EnableClientAccess()]

  20:      public class ItemService : LinqToEntitiesDomainService<BirdLLEntities>

  21:      {

22:

  23:          // TODO:

  24:          // Consider constraining the results of your query method.  If you need additional input you can

  25:          // add parameters to this method or create additional query methods with different names.

  26:          // To support paging you will need to add ordering to the 'tblItems' query.

  27:          public IQueryable<tblItem> GetTblItems()

  28:          {

  29:              return this.ObjectContext.tblItems;

  30:          }

31:

  32:          public void InsertTblItem(tblItem tblItem)

  33:          {

  34:              if ((tblItem.EntityState != EntityState.Detached))

  35:              {

  36:                  this.ObjectContext.ObjectStateManager.ChangeObjectState(tblItem, EntityState.Added);

  37:              }

  38:              else

  39:              {

  40:                  this.ObjectContext.tblItems.AddObject(tblItem);

  41:              }

  42:          }

43:

  44:          public void UpdateTblItem(tblItem currenttblItem)

  45:          {

  46:              this.ObjectContext.tblItems.AttachAsModified(currenttblItem, this.ChangeSet.GetOriginal(currenttblItem));

  47:          }

48:

  49:          public void DeleteTblItem(tblItem tblItem)

  50:          {

  51:              if ((tblItem.EntityState == EntityState.Detached))

  52:              {

  53:                  this.ObjectContext.tblItems.Attach(tblItem);

  54:              }

  55:              this.ObjectContext.tblItems.DeleteObject(tblItem);

  56:          }

57:

  58:          /// <summary>

  59:          /// Gets the TBL items by item number.

  60:          /// </summary>

  61:          /// <param name="itemnumber">The itemnumber.</param>

  62:          /// <returns></returns>

  63:          public IQueryable<tblItem> GetTblItemsByItemNumber(int itemnumber)

  64:          {

  65:              return this.ObjectContext.tblItems.Where(i => i.ItemNumber == itemnumber);

  66:          }

  67:      }

另一个是Metadata :

   1:  namespace RIAServices.Web

   2:  {

   3:      using System;

   4:      using System.Collections.Generic;

   5:      using System.ComponentModel;

   6:      using System.ComponentModel.DataAnnotations;

   7:      using System.Linq;

   8:      using System.ServiceModel.DomainServices.Hosting;

   9:      using System.ServiceModel.DomainServices.Server;

10:

  11:      // The MetadataTypeAttribute identifies tblItemMetadata as the class

  12:      // that carries additional metadata for the tblItem class.

  13:      [MetadataTypeAttribute(typeof(tblItem.tblItemMetadata))]

  14:      public partial class tblItem

  15:      {

16:

  17:          // This class allows you to attach custom attributes to properties

  18:          // of the tblItem class.

  19:          //

  20:          // For example, the following marks the Xyz property as a

  21:          // required property and specifies the format for valid values:

  22:          //    [Required]

  23:          //    [RegularExpression("[A-Z][A-Za-z0-9]*")]

  24:          //    [StringLength(32)]

  25:          //    public string Xyz { get; set; }

  26:          internal sealed class tblItemMetadata

  27:          {

28:

  29:              // Metadata classes are not meant to be instantiated.

  30:              private tblItemMetadata()

  31:              {

  32:              }

33:

  34:              public string ItemDescription { get; set; }

35:

  36:              public int ItemNumber { get; set; }

37:

  38:              public Nullable<int> Quantity { get; set; }

  39:          }

  40:      }

  41:  }

然后打开Data—>Show Data Source，如下图：

然后打开另一个Project中Mainpage.xaml，我们之前应用生成这样的XMAL:

   1:  <UserControl x:Class="RIAServices.MainPage"

   2:      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

   3:      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

   4:      xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

   5:      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

   6:      mc:Ignorable="d"

   7:      d:DesignHeight="536" d:DesignWidth="463" xmlns:riaControls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.DomainServices" xmlns:my="clr-namespace:RIAServices.Web" xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk">

8:

   9:      <Grid x:Name="LayoutRoot" Background="White" Height="536" Width="463">

  10:          <Grid.ColumnDefinitions>

  11:              <ColumnDefinition Width="140*" />

  12:              <ColumnDefinition Width="47*" />

  13:              <ColumnDefinition Width="405*" />

  14:          </Grid.ColumnDefinitions>

  15:          <riaControls:DomainDataSource AutoLoad="False" d:DesignData="{d:DesignInstance my:tblItem, CreateList=true}" Height="0" LoadedData="tblItemDomainDataSource_LoadedData" Name="tblItemDomainDataSource" QueryName="GetTblItemsQuery" Width="0" Margin="0,0,140,393">

  16:              <riaControls:DomainDataSource.DomainContext>

  17:                  <my:ItemContext />

  18:              </riaControls:DomainDataSource.DomainContext>

  19:          </riaControls:DomainDataSource>

  20:          <sdk:DataGrid AutoGenerateColumns="False" Height="181" HorizontalAlignment="Left" ItemsSource="{Binding ElementName=tblItemDomainDataSource, Path=Data}" Name="tblItemDataGrid" RowDetailsVisibilityMode="VisibleWhenSelected" VerticalAlignment="Top" Width="400" Margin="0,58,0,0" Grid.ColumnSpan="3">

  21:              <sdk:DataGrid.Columns>

  22:                  <sdk:DataGridTextColumn x:Name="itemDescriptionColumn" Binding="{Binding Path=ItemDescription}" Header="Item Description" Width="SizeToHeader" />

  23:                  <sdk:DataGridTextColumn x:Name="itemNumberColumn" Binding="{Binding Path=ItemNumber, Mode=OneWay}" Header="Item Number" IsReadOnly="True" Width="SizeToHeader" />

  24:                  <sdk:DataGridTextColumn x:Name="quantityColumn" Binding="{Binding Path=Quantity}" Header="Quantity" Width="SizeToHeader" />

  25:              </sdk:DataGrid.Columns>

  26:          </sdk:DataGrid>

  27:          <Button Content="Query" Height="23" HorizontalAlignment="Left" Margin="171,12,0,0" Name="btnquery" VerticalAlignment="Top" Width="75" Click="btnquery_Click" Grid.Column="2" />

  28:          <TextBox Height="23" HorizontalAlignment="Left" Margin="1,12,0,0" Name="txtItemNumber" VerticalAlignment="Top" Width="120" Grid.ColumnSpan="2" />

  29:          <sdk:DataGrid AutoGenerateColumns="False" Height="179" HorizontalAlignment="Left" ItemsSource="{Binding ElementName=tblItemDomainDataSource, Path=Data}" Margin="1,320,0,0" Name="dataGrid1" RowDetailsVisibilityMode="VisibleWhenSelected" VerticalAlignment="Top" Width="400" Grid.ColumnSpan="3">

  30:              <sdk:DataGrid.Columns>

  31:                  <sdk:DataGridTextColumn x:Name="dataGridTextColumn1" Binding="{Binding Path=ItemDescription}" Header="Item Description" Width="SizeToHeader" />

  32:                  <sdk:DataGridTextColumn x:Name="dataGridTextColumn2" Binding="{Binding Path=ItemNumber, Mode=OneWay}" Header="Item Number" IsReadOnly="True" Width="SizeToHeader" />

  33:                  <sdk:DataGridTextColumn x:Name="dataGridTextColumn3" Binding="{Binding Path=Quantity}" Header="Quantity" Width="SizeToHeader" />

  34:              </sdk:DataGrid.Columns>

  35:          </sdk:DataGrid>

  36:          <sdk:Label Grid.ColumnSpan="3" Height="21" HorizontalAlignment="Left" Margin="1,281,0,0" Name="label1" VerticalAlignment="Top" Width="189" Content="CustomerService from ADO.NET" />

  37:      </Grid>

  38:  </UserControl>

为了对比我们建立另一个自定义DomainService, 也需要建立一个Entity:

   1:  using System;

   2:  using System.Collections.Generic;

   3:  using System.ComponentModel;

   4:  using System.ComponentModel.DataAnnotations;

   5:  using System.Linq;

   6:  using System.ServiceModel.DomainServices.Hosting;

   7:  using System.ServiceModel.DomainServices.Server;

8:

   9:  namespace RIAServices.Web

  10:  {

  11:      public class Item

  12:      {

  13:          [Key]

  14:          public int ItemNumber { get; set; }

  15:          public string ItemDescription { get; set; }

  16:          public Nullable<int> Quantity { get; set; }

  17:      }

  18:  }

CustomerDomainService，里面我们使用原生态的ADO.NET进行数据访问，你也可以替代成你自己的数据Provider.

   1:      [EnableClientAccess()]

   2:      public class CustomerDomainService : DomainService

   3:      {

   4:          public List<Item> GetItemsFromDatabase()

   5:          {

   6:              SqlConnection sqlConnection = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["MainDb"].ToString());

   7:              DataSet objSet = new DataSet();

   8:              SqlCommand sqlCommand = new SqlCommand();

   9:              sqlCommand.Connection = sqlConnection;

  10:              sqlCommand.CommandText = "Select * FROM tblItem";

  11:              SqlDataAdapter sqlDataAdapter = new SqlDataAdapter();

  12:              sqlDataAdapter.SelectCommand = sqlCommand;

  13:              sqlDataAdapter.Fill(objSet);

14:

  15:              List<Item> lstResult = new List<Item>();

  16:              Item objEmployee;

17:

  18:              if (objSet.Tables.Count > 0)

  19:              {

  20:                  foreach (DataRow dr in objSet.Tables[0].Rows)

  21:                  {

  22:                      objEmployee = new Item();

  23:                      objEmployee.Quantity = Convert.ToInt32(dr["Quantity"]);

  24:                      objEmployee.ItemDescription = dr["ItemDescription"].ToString();

  25:                      objEmployee.ItemNumber = Convert.ToInt32(dr["ItemNumber"]);

  26:                      lstResult.Add(objEmployee);

  27:                  }

  28:              }

  29:              return lstResult;

  30:          }

  31:      }

最后我们来看MainPage.xaml.cs 的代码：

   1:     public partial class MainPage : UserControl

   2:      {

   3:          public MainPage()

   4:          {

   5:              InitializeComponent();

6:

   7:              var itemContext = new ItemContext();

   8:              tblItemDataGrid.ItemsSource = itemContext.tblItems;

   9:              EntityQuery<tblItem> s = itemContext.GetTblItemsQuery();

  10:              LoadOperation<tblItem> op = itemContext.Load(s);

11:

  12:              //Use another domain service

  13:              var customerservice = new CustomerDomainContext();

  14:              dataGrid1.ItemsSource = customerservice.Items;

  15:              EntityQuery<Item> s2 = customerservice.GetItemsFromDatabaseQuery();

  16:              LoadOperation<Item> op2 = customerservice.Load(s2);

17:

  18:          }

19:

  20:          private void tblItemDomainDataSource_LoadedData(object sender, System.Windows.Controls.LoadedDataEventArgs e)

  21:          {

  22:              if (e.HasError)

  23:              {

  24:                  System.Windows.MessageBox.Show(e.Error.ToString(), "Load Error", System.Windows.MessageBoxButton.OK);

  25:                  e.MarkErrorAsHandled();

  26:              }

  27:          }

28:

  29:          /// <summary>

  30:          /// Handles the Click event of the btnquery control.

  31:          /// </summary>

  32:          /// <param name="sender">The source of the event.</param>

  33:          /// <param name="e">The <see cref="System.Windows.RoutedEventArgs"/> instance containing the event data.</param>

  34:          private void btnquery_Click(object sender, RoutedEventArgs e)

  35:          {

  36:              var tt = new ItemContext();

  37:              tblItemDataGrid.ItemsSource = tt.tblItems;

  38:              EntityQuery<tblItem> s = tt.GetTblItemsByItemNumberQuery(txtItemNumber.Text == "" ? 0 : Convert.ToInt32(txtItemNumber.Text));

  39:              LoadOperation<tblItem> op = tt.Load(s);

  40:          }

41:

  42:      }

这里我们禁用了默认SilverLight DataGrid的自动绑定，在InitializeComponent方法后增加了代码绑定。btnquery_Click方法对应的是UI上那个Button的Click事件，用来做数据查询。
另一个要注意是ItemService中的GetTblItemsByItemNumber方法是后面加入的，其它方法是自动生成的。最后F5运动后效果是：

简单查询的结果:

这个后面访问了WCF Service地址是:

http://localhost:54934/Services/RIAServices-Web-ItemService.svc

通过Monitor我们看到GetItemsFromDatabase方法返回的数据是:

@GetItemsFromDatabaseResponsehttp://tempuri.org/@GetItemsFromDatabaseResult    aDomainServices    i)http://www.w3.org/2001/XMLSchema-instance^

TotalCount?^ RootResults    b7http://schemas.datacontract.org/2004/07/RIAServices.Web_Item_ItemDescription?Item Name1_

ItemNumber僟Quantity?_Item_ItemDescription?Item Name2_

ItemNumber?_Quantity?_Item_ItemDescription?Item Name3_

ItemNumber?_Quantity?_Item_ItemDescription?Item Name4_

ItemNumber?_Quantity?_Item_ItemDescription?Item Name5_

ItemNumber?_Quantity?_Item_ItemDescription?Item Name6_

ItemNumber?_Quantity?

这是WCF RIA Service默认的数据格式。有时间将在以后解析它们。希望对您的开发有帮助。

作者：Petter Liu
出处：http://www.cnblogs.com/wintersun/
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。
该文章也同时发布在我的独立博客中-Petter Liu Blog。

来源：https://www.cnblogs.com/wintersun/archive/2010/10/21/1857731.html

标签

wcf

services

silverlight