Using Autofac With Web API

Now, new dialog will pop up to select the template. We are going to choose Web API template and click OK button.

Now, we need to create a class library. To do this, right click on the project name > Add > New Item > select class library.

After creating our class library, we are going to add ADO.NET Entity Data Model.

Adding ADO.NET Entity Data Model

For this, right click on the class library name, click Add > Add New Item. The dialog box will pop up inside Visual C#, select Data, followed by ADO.NET Entity Data Model and enter the name for your DbContext model as CustomerModel. finally click Add.

At this stage, we are going to choose EF Designer from the database, as given below.

In the snapshot given below, we need to select your Server name, then via dropdown list in connect to a database section, you should choose your database name, finally click OK button.

As given above, the dialog Entity Data Model Wizard will pop up to choose an object, which is used in the demo. In this example, we are going to select Customer table and click Finish button.

Finally, we see that EDMX model generates Customer entity, as shown below.

Now, we are going to create generic repository, which contains the method used to return all the data from customer table. I would like to say that the following repository can also include any other methods like (CRUD, etc.)

First of all, we are creating Db Factory class, which returns the instance of DbContext.

IDbFactory.cs

DbFactory.cs

IGenericRepository.cs

GenericRepository.cs

After implementing generic repository, we are adding reference of our class library to Web API project. To do this, right click on References > Add Reference.

Installing Autofac

It’s simple to add Autofac. We can do this by using NuGet Packages or Package Manager Console. In this example, I used NuGet Packages. Thus, right click on References > Manage NuGet Packages.

First, we are installing Autofac. Subsequently, install Autofac.integration.WebAPI, as shown below.

Note

Please make sure that the references given below have been added successfully.

Create a controller

Now, we are going to create a controller. Right click on the controllers folder > Add > Controller> selecting Web API 2 Controller – Empty > click Add.

Enter Controller name (‘CustomerController’).

CustomerController.cs

As you can see, we have injected our customer repository within constructor, and then we have defined method called Get Customer List which returns Customer list.

Configuring Autofac

At this point, from Solution Explorer section, we are going to add 2 classes, as shown below.

AutofacWebapiConfig.cs

Here, you register the components with Autofac by creating a container builder, which components expose, which services.

In RegisterServices() method, we have registered all the needed types that expose interfaces. Now, build the container to finalize the registrations and prepare for the object resolution.

In Initialize() method, after building your container, we need to pass it into new instance of the AutofacWebApiDependencyResolver class. Attach the new resolver to your config.DependencyResolver to allow Web API know that it should locate the Services, using the AutofacWebApiDependencyResolver.

Bootstrapper.cs

Note

Please make sure that Run() has been added in Application_Start() method.

Global.asax.cs

Output

Now, you can run your Application and let’s see the output.