Difference between ASP.NET MVC 3 and ASP.NET MVC 4

1. S.No ASP.NET MVC 3
1
ASP.NET MVC 4
Whether Bundling and Minification
Whether Bundling and Minification
feature is supported in ASP.NET MVC 3? feature is supported in ASP.NET MVC 4?
No
Yes
What is Bundling and Minification?Why
they are important?
It reduces number of HTTP requests that a
web page needs to make. Bundling and
Minification combines individual files into
single, bundled file for scripts and CSS and
then reduce the overall size by minifying the
contents of the bundle.
2
Whether Display Modes feature is
supported in ASP.NET MVC 3?
No
Whether Display Modes feature is
supported in ASP.NET MVC 4?
Yes
What are Display Modes?
Display Modes is new feature provided in
ASP.NET MVC 4. It lets an application select
views depending on the browser which is
making request. For example, if a desktop
browser requests home page of an application
it will return ViewsHomeIndex.cshtml view
and if a mobile browser requests home page it
will return ViewsHomeIndex.mobile.cshtml
view.
3
Empty MVC Project template in
ASP.NET MVC 3:
The ASP.NET MVC 3 Empty project
template is not really empty. It contains css
and js files.
Empty MVC Project template in ASP.NET
MVC 4:
The ASP.NET MVC 4 Empty project
template is really empty. It does not contain
any css and js files.
4
Custom Controllers in ASP.NET MVC 3: Custom Controllers in ASP.NET MVC 4:
In ASP.NET MVC 3 we can only place
In ASP.NET MVC 4 we can place custom
custom controllers inside the Controllers
controller to custom locations.
folder.
5
Whether WebSockets and SignalR
features are supported in ASP.NET MVC
3?
No
Whether WebSockets and SignalR
features are supported in ASP.NET MVC
4?
Yes
What are WebSockets and SignalR?
ASP.NET MVC 4 supports WebSockets along
with the new open source framework SignalR
which allows to set up real time multi-user

2. communication through open TCP sockets.
6
Whether Recipe feature is supported in
ASP.NET MVC 3?
No
Whether Recipe feature is supported in
ASP.NET MVC 4?
Yes
What are Recipes and provide their
significance?
In technical language ASP.NET MVC 4
recipe is nothing but a dialog box that is
delivered via NuGet with associated UI and
code used to automate specific task. It’s like
GUI for NuGet Package Manager. Recipes
are set of assemblies which are loaded
dynamically by Managed Extensibility
Framework (MEF). MEF provides plugin
model for applications. The main use of
recipes are to automate development task,
tasks that are encapsulated into recipes and
used over and over again. For example,
adding ajax grid to view or manipulating
multiple areas of the application can be
automated using ASP.NET MVC 4 recipes.
7
Is it possible to provide authentication
using popular sites like Facebook or
twitter into the web application using
ASP.NET MVC 3?
No
Is it possible to provide authentication
using popular sites like Facebook or twitter
into the web application using ASP.NET
MVC 4?
Yes
How it can be done?
Using DotNetOpenAuth library we can
provide authentication using OAuth or
OpenID providers. In ASP.NET MVC 4
Internet project template includes this library.
8
Whether Mobile Project Template is
available in ASP.NET MVC 3?
No
Whether Mobile Project Template is
available in ASP.NET MVC 4?
Yes
Why separate mobile project template
while you can render your web application
in mobile without additional
customization?
The mobile project template touch-optimized
UI using jQuery.Mobile.MVC NuGet
Package for smart phones and tablets.
9
Asynchronous controller implementation
in ASP.NET MVC 3?
In ASP.NET MVC 3, to implement
asynchronous controller/methods we need to
Asynchronous controller implementation
in ASP.NET MVC 4?
The ASP.NET MVC 4 Controller class in
combination .NET 4.5 enables us to write

3. derive controller from AsyncController
rather than from plain Controller class. We
need to create two action methods rather
than one. Fist with suffix “Async” keyword
and second with “Completed” suffix. The
method which initiated asynchronous
process must end with “Async” and the
method which is invoked when the
asynchronous process finishes must end
with “Completed”.
Example:
Please look at the bottom of the table
asynchronous action methods that return an
object of type Task. The .NET Framework 4
introduced an asynchronous programming
concept referred to as a Task and ASP.NET
MVC 4 supports Task. The .NET Framework
4.5 builds on this asynchronous support with
the await and async keywords that make
working with Task objects much less complex
than previous asynchronous approaches. The
await keyword is syntactical shorthand for
indicating that a piece of code should
asynchronously wait on some other piece of
code. The async keyword represents a hint
that we can use to mark methods as taskbased asynchronous methods. To implement
asynchronous action method in ASP.NET
MVC 4 we do no need to derive our
controller class from AsyncController, async
and await in cooperation with Task will do
the magic. To mark the action method
asynchronous use async in method signature.
To wait for the other method to finish use
await and to call multiple parallel methods
use Task. The asynchronous method will
return Task instead of plain ActionResult.
Example:
Please look at the bottom of the table
10
Enhancement in Default Project
Template:
The enhanced default project template is
modern-looking. Along with cosmetic
enhancements, it also employs adaptive
rendering to look nice in both desktop and
mobile browsers without need of any kind
of additional customization.
Enhancement in Default Project Template:
Not Applicable
11
Whether ASP.NET Web API is available
in ASP.NET MVC 3?
No
Whether ASP.NET Web API is available in
ASP.NET MVC 4?
Yes
What is ASP.NET Web API?
ASP.NET MVC 4 includes ASP.NET Web
API, a new framework for creating HTTP
services that can reach a broad range of
clients including browsers and mobile
devices. ASP.NET Web API is also an ideal
platform for building RESTful services.
12
Whether Windows Azure feature is
supported in ASP.NET MVC 3?
Whether Windows Azure feature is
supported in ASP.NET MVC 4?

4. No
Yes
It supports Windows Azure SDK1.6 and new
releases.
What is Windows Azure?
Windows Azure is an open and flexible cloud
platform that serves as the development, data
storing, service hosting and service
management environment. Windows Azure
provides developers with on-demand compute
and storage to host, scale, and manage web
applications on the internet through Microsoft
data-centers.
Example for Asynchronous controller implementation in ASP.NET MVC 3 :
Example for Asynchronous controller implementation in ASP.NET MVC 4 :
Here the await keyword does not block the thread execution until the task is complete. It signs up
the rest of the method as a callback on the task, and immediately returns. When the awaited task
eventually completes, it will invoke that callback and thus resume the execution of the method right
where it left off.

5. Reference:
http://onlydifferencefaqs.blogspot.in/2014/02/difference-between-aspnet-mvc-3-and.html