EF Database First with ASP.NET MVC: Generating Views
Using MVC, Entity Framework, and ASP.NET Scaffolding, you can create a web application that provides an interface to an existing database. This tutorial series shows you how to automatically generate code that enables users to display, edit, create, and delete data that resides in a database table. The generated code corresponds to the columns in the database table.
This part of the series focuses on using ASP.NET Scaffolding to generate the controllers and views.
Add scaffold
You are ready to generate code that will provide standard data operations for the model classes. You add the code by adding a scaffold item. There are many options for the type of scaffolding you can add; in this tutorial, the scaffold will include a controller and views that correspond to the Student and Enrollment models you created in the previous section.
To maintain consistency in your project, you will add the new controller to the existing Controllers folder. Right-click the Controllers folder, and select Add – New Scaffolded Item.
Select the MVC 5 Controller with views, using Entity Framework option. This option will generate the controller and views for updating, deleting, creating and displaying the data in your model.
Set the controller name to StudentController, select Student for the model class, and select the ContosoUniversityEntities for the context class.
Click Add.
If you receive an error, it may be because you did not build the project in the previous section. If so, try building the project, and then add the scaffolded item again.
After the code generation process is complete, you will see a new controller and views in your project.
Perform the same steps again, but add a scaffold for the Enrollment class. When finished, you should have an EnrollmentController.cs file, and a folder under Views named Enrollment with the Create, Delete, Details, Edit and Index views.
Display student views
You will verify that the code added to your project correctly displays a list of the students, and enables users to edit, create, or delete the student records in the database.
Right-click the Views/Student/Index.cshtml file, and select View in Browser. Notice that it displays a list of the students.
Click the Create New link and provide some values for a new student.
Click Create, and notice the new student is added to your list.
Select the Edit link, and change some of the values for a student.
Click Save, and notice the student record has been changed.
Finally, select the Delete link and confirm that you want to delete the record by clicking the Delete button.
Close the browser.
Without writing any code, you have added views that perform common operations on the data in the Student table.
Display enrollment views
Your database includes a one-to-many relationship between the Student and Enrollment tables, and a one-to-many relationship between the Course and Enrollment tables. The views for Enrollment correctly handle these relationships. Right-click Views/Enrollment/Create.cshtml and select View in Browser. The view displays a form for creating a new enrollment record. In particular, notice that the form contains two drop-down lists that are populated with values from the related tables.
Furthermore, validation of the provided values is automatically applied based on the data type of the field. Grade requires a number, so an error message is displayed if you try to provide an incompatible value.
You have verified that the automatically-generated views enable users to work with the data in the database. In the next tutorial in this series, you will update the database and make the corresponding changes in the web application.
Author Information
Tom FitzMacken – Tom FitzMacken is a Senior Programming Writer on the Web Platform & Tools Content team.
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