Heads up! To view this whole video, sign in with your Courses Plus account or enroll in your free 7-day trial. Sign In Enroll

Preview

Start a free Courses trial
to watch this video

Sign up for Treehouse

What is ASP.NET Core?

7:22 with James Churchill

ASP.NET Core is a new open-source and cross-platform web framework from Microsoft. In this video, we'll take a closer look at ASP.NET Core, how if differs from previous versions of ASP.NET, and an overview of the features and benefits it offers.

[MUSIC] 0:00
Hi there. 0:04
This is James. 0:05
I'm a developer and teacher at tree house. 0:06
In this workshop we'll be taking a look at ASP.NET core, 0:09
Microsoft's latest web framework. 0:13
We'll start with answering the question, what is ASP.NET Core? 0:15
From the official documentation, ASP.Net Core is a new, open-source and 0:20
cross-platform framework for building modern cloud based Internet connected 0:25
applications, such as web apps, IoT apps, and mobile backends. 0:30
ASP.Net Core is a significant redesign of ASP.Net. 0:35
It's the biggest release of ASP.NET since version 1.0. 0:40
While some parts of ASP.NET Core will feel familiar such as MVC Controllers and 0:44
Views, other parts will seem completely new. 0:49
ASP.NET Core is a complete rewrite of the ASP.NET web framework. 0:52
It's no longer based on the System.Web assembly. 0:58
Breaking away from ASP.NET legacy code was necessary in order for 1:01
the ASP.NET development team to meet their stated design goals 1:06
of producing a fast cross-platform cloud friendly web framework. 1:10
ASP.NET Core places the focus on MVC and 1:14
Web API which have been merged into a single API. 1:18
We'll take a closer look at the convergence of MVC and 1:22
Web API later in this workshop. 1:25
Web forms and webpages are not currently available in ASP.NET Core, 1:27
nor are they likely ever to be. 1:32
Microsoft has made it clear that web forms and web pages will 1:35
remain as part of the full .NET framework and not brought into ASP.NET Core. 1:40
The ASP.NET team does have a new feature on the roadmap named view pages 1:45
that is similar to the functionality of web pages. 1:50
See the teacher's notes for more information. 1:53
ASP.NET Core runs on either .NET Core or the full .NET framework. 1:55
This gives you the flexibility to choose the target framework 2:01
that makes the most sense for your situation. 2:04
.NET Core is a new cross-platform version of .NET that runs on Windows, 2:06
Linux or Mac OS. 2:12
.NET Core has a flexible deployment model that gives you the option to deploy it 2:14
along with your application in addition to the more traditional side-by-side user or 2:19
machine-wide deployment options. 2:24
Only a subset of the .NET frameworks API surface has been implemented in .NET Core. 2:27
For instance, 2:32
the system drawing namespace is currently only partially implemented in .NET Core. 2:33
If your application needs to manipulate bitmaps 2:39
you'll need to use a third party library that's compatible with .NET core. 2:41
Or target the full .NET Framework. 2:46
.NET Core only supports a single app model, console apps. 2:49
While that might seem limiting, 2:53
it's possible to build other app models on top of it which is what ASP.NET Core does. 2:55
We'll see it later in this workshop how that works. 3:01
The .NET command line interface or CLI shipped as part of the .NET Core SDK. 3:04
The .NET CLI is a set of commands that allows you to create, build, run, 3:10
publish, test and package .NET Core apps all from the command line. 3:16
Having the CLI available, ensures that you can develop .NET Core apps 3:21
including ASP.NET Core apps, regardless of what platform or tools you're using. 3:25
For instance, 3:30
you can develop apps on Linux using the text editor of your choice. 3:31
CLI is even used by Visual Studio. 3:36
When using Visual Studio to develop .NET Core apps Visual Studio 3:39
delegates to the .NET CLI to build, run and publish your app. 3:43
ASP.NET Core and .NET Core are fully open source projects being hosted on GitHub. 3:48
Development is being done completely out in the open. 3:54
You can monitor or 3:58
contribute to the teams ongoing development discussions via GitHub issues. 3:59
Or you can fork any of the repos, fix a bug or 4:04
implement a feature and issue a poll request against the main repo. 4:07
ASP.NET Core is another example of the new Microsoft. 4:11
A Microsoft that is embracing open source development. 4:16
Unlike previous versions of ASP.NET, 4:20
ASP.NET Core is not a single monolithic assembly. 4:22
Instead it's delivered as a set of granular and well factored NuGet packages. 4:27
This gives you a true pay-for-what-you-use-model. 4:32
You only reference and deploy the packages that your application needs. 4:35
In order to realize ASP.NET Cores cross-platform design goal, 4:40
Microsoft needed a cross-platform server for running ASP.NET Core apps. 4:44
Kestrel is that server. 4:49
Kestrel is a cross-platform, managed web server based on libuv. 4:51
libuv is a multi-platform support library with a focus on 4:56
asynchronous IO that was developed primarily for 5:00
NodeJS, but is used by other projects including now, Kestrel. 5:04
Kestrel is the only supported web server for running ASP.NET Core apps. 5:09
IIS is no longer directly supported, 5:14
meaning that IIS does not host ASP.NET Core apps within its own process. 5:17
Instead IIS is used as a reverse proxy to Kestrel using 5:23
the ASP.NET Core module, HTTP module. 5:28
This is the same overall approach used for hosting NodeJS apps in IIS. 5:32
ASP.NET.Core apps running on Castro have 5:37
been able to achieve amazing performance benchmarks. 5:41
In February 2016 ASP.NET.Core achieved 1.15 million requests per second. 5:44
In a sense exceeded that number. 5:52
To put that number into perspective, 5:54
1.15 million requests per second represents a 2300% 5:58
gain over ASP.NET 4.6 or 800% gain over NodeJS. 6:03
The second decimal place, 0.05 million or 6:08
50,000 is around the total number of requests per second that 6:12
ASP .NET 4.6 could perform of the same type on the same hardware. 6:16
Most applications will never need this kind of throughput. 6:22
But having this kind of headroom will help ensure that your applications feel fast 6:25
and responsive. 6:30
As previously mentioned, ASP.NET Core runs on Windows, Linux, and macOS. 6:32
This is the first time that this is possible 6:38
using Microsoft supported runtimes and frameworks. 6:41
Cross-platform support opens up new development and deployment scenarios, 6:44
including being able to support mixed environment development teams. 6:49
And deploying your applications on to cloud hosted Linux virtual machines or 6:53
containers. 6:58
In this workshop I'll be working with both Windows and macOS. 6:59
To get started with ASP.NET Core development visit the new dot.net website, 7:04
where you can find detailed installation instructions and 7:10
downloadable installers for the platform of your choice. 7:13
In the next video we'll use the .NET CLI to create our first project. 7:17

You need to sign up for Treehouse in order to download course files.

Sign up