Unity Container implementation in MVC Application

I was reading about the dependency injection and unity container for a while but never get a chance to implement it in real project. Luckily, I got a task to design a small audit application and I thought to use the dependency injection design pattern and unity container to inject the dependencies in Lazy binding manner.

I just wanted to share my work with you guys so that you can also take the advantages of unity container. This post will give you the idea how to use the unity container in your future MVC project. Also, I would like to mention that I used the property injection in the example.

Lets get started

Step 1 – First thing first – prerequisite

·         VS 2015

·         Unity.MVC (Get it from nuget. I used 5.0.3 version)

Step 2 – Create a MVC application

Step 3 – Install the Unity.MVC using nugget. After the installation you will see below files get added in project reference

It will add 2 files in App_Start folder

Step 4 – Create an interface. In my case, I exposed 3 abstract method

public interface IAction

    {

        bool SaveData(OperationTypes oprType, object uObject);

        bool UpdateData(OperationTypes oprType, object objLookup);

        bool GetData(OperationTypes oprType);

    }

Step 5 – Create a concrete class (Derived class). Give the method declaration per your need.

public class LoadStatusConcrete : IAction

    {

        bool IAction.GetData(OperationTypes oprType)

        {

            throw new NotImplementedException();

        }

        bool IAction.SaveData(OperationTypes oprType, object uObject)

        {

            throw new NotImplementedException();

        }

        bool IAction.UpdateData(OperationTypes oprType, object objLookup)

        {

            throw new NotImplementedException();

        }

    }

Step 6 – If your plan is to use my code then you need the Enum class as well. Otherwise it will complain

    public enum OperationTypes

    {

        User,

        File,

        Process

    }

Step 7 –We have created all the primary building blocks. We now need to work on the code that is actually going to use these objects. I will first start with Controller file.

Add a new controller to your project and create a property of IAction interface. I am creating the object based on the condition they why I using the “Dependency” attribute and passing the criteria.

Step 8 – Changes to the UnityConfig.cs file. Inside the RegisterTypes method copy the below lines

container.RegisterType<IAction, LookupConcrete>("Lookup");

       container.RegisterType<IAction, LoadStatusConcrete>("Load");

Just in case unity variables are not predefined. Add below line of code inside the UniftConfig class.

        #region Unity Container

        private static Lazy<IUnityContainer> container =

          new Lazy<IUnityContainer>(() =>

          {

              var container = new UnityContainer();

              RegisterTypes(container);

              return container;

          });

        ///

        /// Configured Unity Container.

        ///

        public static IUnityContainer Container => container.Value;

        #endregion

Step 9 – Build and run your MVC application. There are many more options that unity container provide and many different ways you can use it. But I found property injection straight forward and easy to use.