如何从 Visual Studio with Linq 中的 WebMatrix-database 中进行选择

我们如何在Visual Studio中使用Linq从SDF（webmatrix）数据库中选择数据，就像我们在Northwind中一样，像这样：？

// Northwnd inherits from System.Data.Linq.DataContext.
Northwnd nw = new Northwnd(@"northwnd.mdf");
// or, if you are not using SQL Server Express
// Northwnd nw = new Northwnd("Database=Northwind;Server=server_name;Integrated Security=SSPI");
var companyNameQuery =
    from cust in nw.Customers
    where cust.City == "London"
    select cust.CompanyName;
foreach (var customer in companyNameQuery)
{
    Console.WriteLine(customer);
}

参考： http://msdn.microsoft.com/en-us/library/bb399398.aspx

感谢您的帮助。