Walkthrough: Creating a Silverlight Web Part that Displays OData for SharePoint

Article
04/28/2015

SharePoint 2010 exposes its list data by means of OData. In SharePoint, the OData service is implemented by the RESTful service ListData.svc. This walkthrough shows how to create a SharePoint web part that hosts a Silverlight application. The Silverlight application displays SharePoint Announcement list information by using ListData.svc. For more information, see SharePoint Foundation REST Interface and Open Data Protocol.

This walkthrough demonstrates the following tasks:

Creating a Silverlight web part and application by using the Visual Studio project template.
Creating a sample Silverlight application.
Accessing SharePoint list data by using the ListData.svc service.
Referencing the Silverlight application in the Silverlight web part.
Displaying the Silverlight web part in SharePoint.

Note

Your computer might show different names or locations for some of the Visual Studio user interface elements in the following instructions. The Visual Studio edition that you have and the settings that you use determine these elements. For more information, see Customizing Development Settings in Visual Studio.

Prerequisites

You need the following components to complete this walkthrough:

Supported editions of Microsoft Windows and SharePoint. For more information, see Requirements for Developing SharePoint Solutions.
Visual Studio 2012.

Creating a Silverlight Application and Silverlight Web Part

First, create a Silverlight application in Visual Studio. The Silverlight application retrieves data from the SharePoint Announcements list by using the ListData.svc service.

Note

No versions of Silverlight before 4.0 support the required interfaces for referencing SharePoint list data.

To create a Silverlight Application and Silverlight web part

On the menu bar, choose File, New, Project to display the New Project dialog box.
Expand the SharePoint node under either Visual C# or Visual Basic, and then choose the 2010 node.
In the templates pane, choose the SharePoint 2010 Silverlight Web Part template.
In the Name box, enter SLWebPartTest and then choose the OK button.

The SharePoint Customization Wizard dialog box appears.
On the Specify the site and security level for debugging page, enter the URL for the SharePoint server site where you want to debug the site definition, or use the default location (http://system name/).
In the What is the trust level for this SharePoint solution? section, choose the Deploy as a farm solution option button.

Although this example uses a farm solution, Silverlight web part projects can be deployed as either farm or sandboxed solutions. For more information about sandboxed solutions and farm solutions, see Sandboxed Solution Considerations.
In the How do you want to associate the Silverlight Web Part section of the Specify Silverlight Configuration Information page, choose the Create a new Silverlight project and associate it with the web part option button.
Change the Name to SLApplication, set Language to either Visual Basic or Visual C#, and then set Silverlight Version to Silverlight 4.0.
Choose the Finish button. The projects appear in Solution Explorer.

The solution contains two projects: a Silverlight application and a Silverlight web part. The Silverlight application retrieves and displays the list data from SharePoint, and the Silverlight web part hosts the Silverlight application, enabling you to view it in SharePoint.

Customizing the Silverlight Application

Add code and design elements to the Silverlight application.

To customize the Silverlight Application

Add an assembly reference to System.Windows.Data in the Silverlight application. For more information, see How to: Add or Remove References By Using the Add Reference Dialog Box.
In Solution Explorer, open the shortcut menu for References, and then choose Add Service Reference.

Note

If you're using Visual Basic, you must choose the Show All Files icon at the top of Solution Explorer to display the References node.
In the Address box of the Add Service Reference dialog box, enter the URL of your SharePoint site, such as http://MySPSite, and then choose the Go button.

When Silverlight locates the SharePoint OData service ListData.svc, it replaces the address with the full service URL. For this example, http://myserver becomes http://myserver/_vti_bin/ListData.svc.
Choose the OK button to add the service reference to the project, and use the default service name, ServiceReference1.
On the menu bar, choose Build, Build Solution.
Add a new data source to the project based on the SharePoint service. To do this, on the menu bar, choose View, Other Windows, Data Sources.

The Data Sources window shows all of the available SharePoint list data, such as Tasks, Announcements, and Calendar.
Add the Announcements list data to the Silverlight application. You can drag "Announcements" from the Data Sources window onto the Silverlight designer.

This creates a grid control bound to the SharePoint site's Announcements list.
Resize the grid control to fit the Silverlight page.

In the MainPage.xaml code file (MainPage.xaml.cs for Visual C# or MainPage.xaml.vb for Visual Basic), add the following namespace references.

' Add the following three Imports statements.
Imports SLApplication.ServiceReference1
Imports System.Windows.Data
Imports System.Data.Services.Client

// Add the following three using statements.
using SLApplication.ServiceReference1;
using System.Windows.Data;
using System.Data.Services.Client;

Add the following variable declarations at the top of the class.

Private context As TeamSiteDataContext
Private myCollectionViewSource As CollectionViewSource
Private announcements As New DataServiceCollection(Of AnnouncementsItem)()

private TeamSiteDataContext context;
private CollectionViewSource myCollectionViewSource;
DataServiceCollection<AnnouncementsItem> announcements = new DataServiceCollection<AnnouncementsItem>();

Replace the UserControl_Loaded procedure with the following.

Private Sub UserControl_Loaded_1(sender As Object, e As RoutedEventArgs)
    ' The URL for the OData service.
    ' Replace <server name> in the next line with the name of your SharePoint server.
    context = New TeamSiteDataContext(New Uri("http://<server name>/_vti_bin/ListData.svc"))

    ' Do not load your data at design time.
    If Not System.ComponentModel.DesignerProperties.GetIsInDesignMode(Me) Then
        'Load your data here and assign the results to the CollectionViewSource.
        myCollectionViewSource =   DirectCast(Me.Resources("announcementsViewSource"), System.Windows.Data.CollectionViewSource)
        announcements.LoadCompleted += New EventHandler(Of LoadCompletedEventArgs)(AddressOf announcements_LoadCompleted)
        announcements.LoadAsync(context.Announcements)
    End If
End Sub

private void UserControl_Loaded_1(object sender, RoutedEventArgs e)
{
    // The URL for the OData service.
    // Replace <server name> in the next line with the name of your 
    // SharePoint server.
    context = new TeamSiteDataContext(new Uri("https://ServerName>/_vti_bin/ListData.svc"));

    // Do not load your data at design time.
    if (!System.ComponentModel.DesignerProperties.GetIsInDesignMode(this))
    {
        //Load your data here and assign the results to the CollectionViewSource.
        myCollectionViewSource = (System.Windows.Data.CollectionViewSource)this.Resources["announcementsViewSource"];
        announcements.LoadCompleted += new EventHandler<LoadCompletedEventArgs>(announcements_LoadCompleted);
        announcements.LoadAsync(context.Announcements);
    }
}

Be sure to replace the ServerName placeholder with the name of your server that's running SharePoint.

Add the following error-handling procedure.

Private Sub announcements_LoadCompleted(sender As Object, e As LoadCompletedEventArgs)
    ' Handle any errors.
    If e.[Error] Is Nothing Then
        myCollectionViewSource.Source = announcements
    Else
        MessageBox.Show(String.Format("ERROR: {0}", e.[Error].Message))
    End If
End Sub

void announcements_LoadCompleted(object sender, LoadCompletedEventArgs e)
{
    // Handle any errors.
    if (e.Error == null)
    {
        myCollectionViewSource.Source = announcements;
    }
    else
    {
        MessageBox.Show(string.Format("ERROR: {0}", e.Error.Message));
    }
}

Modifying the Silverlight Web Part

Change a property in the Silverlight web part project to enable Silverlight debugging.

To modify the Silverlight web part

Open the shortcut menu for the Silverlight web part project (SLWebPartTest), and then choose Properties.
In the Properties window, choose the SharePoint tab.
If it's not already selected, select the Enable Silverlight debugging (instead of Script debugging) check box.
Save the project.

Testing the Silverlight Web Part

Test the new Silverlight web part in SharePoint to ensure that it displays the SharePoint list data properly.

To test the Silverlight web part

Choose the F5 key to build and run the SharePoint solution.
In SharePoint, on the Site Actions menu, choose New Page.
In the New Page dialog, enter a title, such as SL Web Part Test, and then choose the Create button.
In the page designer, on the Editing Tools tab, choose Insert.
On the tab strip, choose Web Part.
In the Categories box, choose the Custom folder.
In the Web Parts list, choose the Silverlight web part, and then choose the Add button to add the web part to the designer.
After you have made all of the additions to the web page that you want, choose the Page tab, and then choose the Save & Close button on the tool bar.

The Silverlight web part should now be displaying Announcement data from the SharePoint site. By default, the page is stored in the Site Pages list in SharePoint.

Note

When accessing data in Silverlight across domains, Silverlight guards against security vulnerabilities that can be used to exploit web applications. If you encounter problems when accessing remote data in Silverlight, see Making a Service Available Across Domain Boundaries.