Programming .NET 3.5

LINQ to SQL Fundamentals

To get started with LINQ to SQL, open Visual Studio 2008 and create a new Console Application named Simple LINQ to SQL. Once the IDE is open, click View and open the Server Explorer. Make a connection to the AdventureWorksLT database and test that connection, as shown in Figure 9-13.

Figure 9-13. Testing the connection to AdventureWorksLT

The next example illustrates using LINQ. For it to compile, you will need to add a reference to the LINQ components. To do so, click on References in your project and add a reference. This opens the dialog shown in Figure 9-14.

Figure 9-14. Adding System.Data.Linq to the project's references

Click on the .NET tab, then scroll down to and select System.Data.Linq. You are now ready to test Example 9-8, which illustrates an extremely stripped-down LINQ connection to a SQL database (in this case, AdventureWorksLT). The mapping between a class property and a database column is accomplished, as you'll see in the listing, by using the column attribute. A full analysis follows.

Example 9-8. Simple LINQ to SQL

using System;
using System.Data.Linq;
using System.Data.Linq.Mapping;
using System.Linq;

namespace Simple_Linq_to_SQL
{
   // Customer class
   [Table(Name="SalesLT.Customer")]
   public class Customer
   {
      [Column] public string FirstName { get; ...