NInjectDI Container

Bhushan Mulmule | bhushan.mulmule@gmail.com | http://dotnetvideotutorial.com

I f you are new to DI Cl ick here to view

Dependency Inject ion for Beginners

And then come back!

If link will not work you can copy and paste following url:http://www.slideshare.net/bhushanmulmule/dependency-injection-for-beginners-31272832

Let us create sample ASP.NET MVC

application to see DI in action

We will be using

ASP.NET MVC Application

To Demonstrate NInject

Follow the Walkthrough to create one

Create New ASP.NET MVC Project: DIContainerDemo

Select Empty Template and Razor View Engine

Add Three Classes and One Interface

INotification

EmailNotification

SMSNotification

Booking

Add New Controller: HomeController

Inject object of EmailNotification

to constructor of Booking

To create Object of Booking

class in HomeController

HomeController

Right Click on Index Method of HomeController Add View

Modify Views/Home/Index.cshtml

Final Structure

And the Output will be…

Inject object of SMSNotification

to constructor of Booking

To create Object of Booking

class we can also

Modified HomeController to use SMSNotification

Output will be…

Dependency Injection!

Problems…

DI Container

DI container is about removing need of

this object instantiation from client code.

Unity, Ninject, Autofac,

StructureMap, Spring.NET

Few of the DI Containers are

NInject

Or you can also download dll and add the reference

Installing NInject

Steps to Set it up

Getting object of bounded concrete class

INotification notification = kernel.Get<INotification>();

Binding interface with concrete class

kernel.Bind<INotification>().To<EmailNotification>();

Creating NInject kernel object

IKernel kernel = new StandardKernel();

Modified HomeController to use NInject

Output as expected…

Note: It will act as centralized location for all Ninject configuration.

Create Folder DIResolver Add class NInjectDependencyResover.cs

NInjectDependencyResolver.cs

Register our Dependency Resolver in Gloabal.aspx

Modify HomeController to use DependencyResolver

Time to enjoy fruits of labor

Lets try to understand

What's happening behind the scene

Steps break up…

Note that GetService() receives type parameter in this case it will be HomeController.

MVCNinject

DependecyResolver

type HomeController

Client Request for index

method of HomeController

MVCNinject

DependecyResolver

Ninject

type HomeController type HomeController

Client Request for index

method of HomeController

MVCNinject

DependecyResolver

Ninject

type HomeController type HomeController

Client Request for index

method of HomeController

Inspects constructor of

HomeController for dependencies

Note: Here Ninject will create object of EmailNotification as we have bounded it to INotification in AddBinding() method. Same way it can be bounded to SMSNotification.

MVCNinject

DependecyResolver

Ninject

type HomeController type HomeController

Object HomeControllerWith

Object EmailNotification

Object HomeControllerwith

Object EmailNotification

Client Request for index

method of HomeController

Inspects constructor of

HomeController for dependencies

“Test Driven Development using Unit

Testing”.

kernel.Bind<INotification>().To<SMSNotification>().WithConstructorArgument("Param", "value");

kernel.Bind<INotification>().To<SMSNotification>().WithPropertyValue("PropertyName", "Value");

Find it out

kernel.Bind<INotification>().To<SMSNotification>().When(//"lamda expression returning bool");

kernel.Bind<INotification>().To<SMSNotification>().WhenClassHas</*attribute type*/>();

.WhenInjectedInto()

.WhenMemberHas()

.WhenTargetHas()

.WhenAnyAnchestorNamed()

Few more…

http://www.ninject.org/learn.html

Credits:

Apress Pro

ASP.NET MVC 4

http://dotnetvideotutorial.com

Thank YouBhushan Mulmule | bhushan.mulmule@gmail.com | http://dotnetvideotutorial.com