210Microsoft Visual Studio 2010: A Beginner’s Guide

VB:

Dim myShop As New MyShopDataContext

Dim customers As IEnumerable = myShop.GetCustomers()

For Each custOrd In customers

Console.WriteLine("Name: " & custOrd.Name)

Next

And here’s the output:

Name: Meg

Name: Joe

Name: May

Just call myShop.GetCustomers and you’ll receive a collection of Customer objects. There are many more advanced scenarios that you can handle with LINQ, but this

is just a beginner’s guide. However, you now have a solid base of query techniques that will get you started. In addition to querying a database, you’ll need to perform insert operations, which is next.

TIP

LINQ to SQL generates SQL (Structured Query Language) statements to send to the database for your queries. If you would like to see the generated SQL, set a breakpoint on the line after the query and run the program with debugging. When you hit the breakpoint, hover over the variable holding query results and you’ll see the SQL statement.

Inserting Data with LINQ to SQL

To insert a new record into a table, you’ll need to create an instance of the LINQ to SQL class for that table, call a method to insert, and then call another method to commit the changes. The following example shows how to add a new record to the Customer table:

C#:

private static int InsertCustomer()

{

var cust = new Customer { Name = "Jim" }; var myShop = new MyShopDataContext(); myShop.Customers.InsertOnSubmit(cust); myShop.SubmitChanges();

return cust.CustomerID;

}

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Microsoft 9GD00001 manual Inserting Data with Linq to SQL