Open the

VirtuosoDataService

project created in the Creating EDM in Visual Studio 2008 section .

Select the Project -> Add New Item menu option.

Figure 8.675. VirtuosoDataService

The

Add New Item

dialog will appear. Choose the

ADO.NET Data Service template

. Give it the name

Virtuoso.svc

, and click

Add

to create the ADO.Net Data Service.

Figure 8.676. Add New Item

In the newly created

Virtuoso.svc.cs

Data Service file, add the data source class name of

VirtuosoEntities

(note this is the name set in the Creating EDM in Visual Studio 2008 section) as the

DataService

name. Enable the access to the Data Service by adding the entry

config.SetEntitySetAccessRule("*", EntitySetRights.All);

in the

InitializeService

method.

// C#

using System;
using System.Web;
using System.Collections.Generic;
using System.ServiceModel.Web;
using System.Linq;
using System.Data.Services;

namespace SimpleDataService
{
    public class Northwind : DataService<VirtuosoDemoEntities>
    {
        public static void InitializeService(IDataServiceConfiguration  config)
        {
            config.SetEntitySetAccessRule("*", EntitySetRights.All);
        }
    }
}

Figure 8.677. Virtuoso.svc.cs

To test the Data Service, simply hit

Ctrl+F5

within Visual Studio. This will start the development web server, run the Data Services server inside and load a Web browser page displaying the list of available tables/entities for the Northwind database catalog.

Figure 8.678. Data Service test

To access a specific entity instance like the

Customers

table ALFKI record, use this convention http://host/vdir/Virtuoso.svc/Customers('ALFKI').

Figure 8.679. EMPLOYEES

Important

- To view

Atom

(the default format returned by an ADO.NET Data Service) in Internet Explorer, you must first ensure that

Feed Reading View

is turned

off

. This can be done on the

Content tab

of

Tools in Internet Options

.

If a Data Services entity instance URI page fails to load you can turn

Verbose

errors on by adding

config.UseVerboseErrors = true;

in the

virtuoso.svc.cs InitializeService

method to obtain more detailed information from the server as to why the page failed to load:

public static void InitializeService(IDataServiceConfiguration config)

{

config.UseVerboseErrors = true;

config.SetEntitySetAccessRule("*", EntitySetRights.All);

}