Enum Support (EF Designer) in Entity Framework 5

Entity Framework 5 brings number of improvements and Enum Support in EF Designer or Code First is one of them. In this post you will learn it by creating a simple console application then will add EF Designer and will sketch the Model on designer surface. Please note, EF Designer can also be used with the Database First workflow to map to an existing database.

Just follow the steps, to setup the demo project.

Step 1: Create New Project

Create a new console application File > New > Project > Visual C# > Console Application.

Step 2: Adding EF Designer (ADO.NET Entity Data Model)

Right click on the project name in ‘Solution Explorer’, point to ‘Add’, and then click ‘New Item’ and in the window select ‘Visual C# Items > and then Data’, now you will find ‘ADO.NET Entity Data Model’ in the Templates pane, add it in the project.



ADO.NET Entity Data Model will bring following things:

EnumTestModel.edmx file that defines the conceptual model, the storage model, and the mapping between them. Sets the Metadata Artifact Processing property of the .edmx file to Embed in Output Assembly so the generated metadata files get embedded into the assembly.

Assemblies files like EntityFramework, System.ComponentModel.DataAnnotations, and System.Data.Entity.

EnumTestModel.tt and EnumTestModel.Context.tt files and adds them under the .edmx file. These T4 template files generate the code that defines the DbContext derived type and POCO types that map to the entities in the .edmx model.

Step 3: Adding New Entity

Right click on Designer and select Add New > Scalar Property. This will bring following window, enter the name ‘Student’ in Entity name box and it will pluralize the Entity Set name (like Students) automatically.



Step 4: Adding Scalar Property

Add ‘Name’ and ‘Course’ scalar properties and make sure to change the ‘Type’ property of ‘Course’ scalar to ‘Int32’. As you know, EF5 enumeration can have the following underlying types only:  Byte, Int16, Int32, Int64 or SByte.



Step 5: Create Enum

Now, right click on ‘Course’ property and click on ‘Convert to Enum’.



In the dialog box use ‘CourseEnum’ in ‘Enum type Name’ and add members and click on OK button.



Step 6: Check Enum in Explorer

Open the Solution Explorer and expand ‘Model1.tt > Courses’, you can also check it from ‘Model Browser’.



Step 7: Data Handling

Now, I all set to retrieve data and for this we need some code in Main() method.



Step 8: Find Database

When you run the application the first time, the Entity Framework creates a database for you. Because we have Visual Studio 2012 installed, the database will be created on the LocalDB instance. By default, the Entity Framework names the database after the fully qualified name of the derived context.

I hope you like it. Thanks.

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