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31 Dec

Like the Getting Started series, this tutorial series uses the ASP. The control gives you more flexibility in other ways as well.

NET Web Forms model and assumes you know how to work with ASP. Because you write your own data-access code, it's easier to do more than just read, insert, update, or delete a specific entity type, which are the tasks that the control is designed to perform.

For an example of how to specify a cascading delete, see The Entity Framework and ASP. page that you will be creating, you want to provide a drop-down list of instructors, with names in "last, first" format so that users can select department administrators.

To make it easier to do that, you will create a view in the database.

In the Tables and Columns dialog box, set the primary key table and field to table if that person is a department administrator.

In a production application, you would provide a specific error message when a database constraint prevents a deletion, or you would specify a cascading delete.

For normal operation, you provide a repository object that works with the Entity Framework.

For testing, you provide a repository object that works with data stored in a way that you can easily manipulate, such as class variables defined as collections.

The Contoso University sample web application demonstrates how to create ASP.

In Visual Studio, open the Contoso University web application you created in the Getting Started with the Entity Framework and Web Forms tutorial series, and then open the table, but no foreign key relationship is defined in the database.

You need to create the relationship and update the data model so that the Entity Framework can automatically handle this relationship.

The pages you create in this tutorial work with the entity set of the data model that you created in the Getting Started tutorial series.

You will begin this tutorial by making two changes to the database, both of which require corresponding changes to the data model that you created in the Getting Started with the Entity Framework and Web Forms tutorials.