与上一个教程一样，将不使用数据库，而是创建一个简单的集合，将以编程方式创建这个集合。这将允许只看到OData部分。
首先，打开项目，在Visual Studio 2010（或更高版本）中，从下面链接的zip文件中打开：
选择“添加”，然后“新建项目...”创建一个新的Silverlight应用程序。添加一个服务引用。点击“发现”。创建一个名为wsSampleCustomerData的引用。接下来，在Silverlight项目中添加以下程序集引用：
在Silverlight项目中，删除MainPage.xaml。打开项目在Expression Blend 4（或更高版本）中。在Expression Blend中，选择“文件”然后“新建项目...”选择“带有ViewModel的用户控件”模板，并创建一个名为MainPage.xaml的文件。它将创建ViewModel页面（MainPage.xaml和MainPage.xaml.cs与一个已经连接的MainPageModel.cs视图模型页面）。
创建一个名为Model的文件夹和一个名为Model.cs的类。用以下代码替换所有代码：
C#
using System;
using System.Linq;
using System.Collections.Generic;
using SilverlightODataSample.wsSampleCustomerData;
using System.Data.Services.Client;
namespace SilverlightODataSample
{
public class Model
{
#region GetCustomers
public static IObservable> GetCustomers(int intPage)
{
// Create a URI that points to theODataService
Uri objUri = new Uri(GetBaseAddress(), UriKind.RelativeOrAbsolute);
// Set up oData service call
SampleDataSource SDS = new SampleDataSource(objUri);
// Construct a Query
var query = (from SampleCustomerData in SDS.SampleCustomerData
where SampleCustomerData.CustomerNotes.Contains("3")
select SampleCustomerData).Skip(intPage).Take(10);
// Set up a DataServiceCollection to hold the results
DataServiceCollection CustomerRecords = new DataServiceCollection();
// Set up a Rx Observable (in a variable called observable)
// that will contain the results of
// the "LoadCompleted" event that CustomerRecords will fire
// When LoadAsync(query) is fired in the following statement
IObservable> observable = Observable.FromEvent(CustomerRecords, "LoadCompleted");
// Execute the LoadAsync on CustomerRecords passing
// the query that was constructed earlier
CustomerRecords.LoadAsync(query);
// Return observable
return observable;
}
#endregion
#region GetBaseAddress
private static string GetBaseAddress()
{
// This gets the address of the webservice by
// getting the AbsoluteUri and then stripping out the
// name of the .xap file
string strXapFile = @"/ClientBin/SilverlightODataSample.xap";
string strBaseWebAddress = App.Current.Host.Source.AbsoluteUri.Replace(strXapFile, "");
return string.Format("{0}/{1}", strBaseWebAddress, "Service.svc");
}
#endregion
}
}
打开MainPageModel.cs并用以下代码替换所有代码：
C#
using System;
using System.ComponentModel;
using System.Collections.ObjectModel;
using SilverlightODataSample.wsSampleCustomerData;
using System.Data.Services.Client;
namespace SilverlightODataSample
{
public class MainPageModel : INotifyPropertyChanged
{
public MainPageModel()
{
// When the Control loads
// Get the Customers
GetCustomers();
}
#region GetCustomers
private void GetCustomers()
{
// Call the Model to get the Customers
// Passing in 0 to get the first page
// Paging could easily be done here
// You could also pass in other criteria
Model.GetCustomers(0).Subscribe(p =>
{
// Check for an error in the Service
if ((p.EventArgs.Error == null))
{
// loop thru each item in the
// DataServiceCollection
// Collection
foreach (CustomerRecord Customer in (DataServiceCollection)p.Sender)
{
// Add to the Customer to the colCustomerRecord
// Collection so the View can bind to it
colCustomerRecord.Add(Customer);
}
}
});
}
#endregion
#region CustomerRecord
// The View will bind to this collection and automatically be notified if
// The collection changes. The Designer can bind any UI element that
// can hold a collection
private ObservableCollection _colCustomerRecord = new ObservableCollection();
public ObservableCollection colCustomerRecord
{
get { return _colCustomerRecord; }
private set
{
if (colCustomerRecord == value)
{
return;
}
_colCustomerRecord = value;
this.NotifyPropertyChanged("colCustomerRecord");
}
}
#endregion
#region INotifyPropertyChanged
// This is a supporting method to raise a notification for any
// Element that is subscribed to a Property that implements
// NotifyPropertyChanged
public event PropertyChangedEventHandler PropertyChanged;
private void NotifyPropertyChanged(String info)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(info));
}
}
#endregion
}
}
抓取一个DataGrid并将其拖放到设计表面上。将其加宽以填充页面。点击“数据”选项卡，以便看到数据上下文。将colCustomerRecord集合拖放到DataGrid上。构建并运行项目。