.NET CoreHow to migrate and write new code for .NET Core

Bertrand Le Roy

▪ Senior Program Manager on .NET Core

▪ One of the founders of Orchard

▪ http://weblogs.asp.net/bleroy

▪ https://blogs.msdn.microsoft.com/dotnet/tag/week-in-net/

▪ https://www.youtube.com/channel/UCvtT19MZW8dq5Wwfu6B0oxw

Objectives

▪ What’s .NET Core and when to use it (or not)

▪ How to create a new library, ASP.NET, or console application

▪ How to port existing code

Innovation

Any platformOpenness

.NET CoreASP.NET 5

.NET Core ≠ .NET Framework

.NET Framework 4.6

▪ .NET implementation for any scenario on Windows with comprehensive library support

.NET Core

▪ Modular and smaller implementation of .NET

▪ Cross-platform▪ App-level isolation▪ Built in the open▪ Optimized for specific workloads▪ Built for the next ten years of software development

WPF Windows Forms

Universal Windows Apps

ASP.NET (4.X) ASP.NET Core

Next gen JIT (RyuJIT)SIMD

Runtime Components Compilers

Languages innovation.NET Compiler Platform

.NET Core 5 Libraries

.NET Framework 4.6 Libraries

NuGet packagesCommon

.NET Framework 4.6 .NET Core

What’s common, and what’s not?

What’s not supported?

▪ WPF

▪ Winforms

▪ WebForms

▪ Binary serialization…

▪ Anything Windows-specific: registry, ACLs, perf counters, etc.

Significant change: Reflection

foo.GetType() → foo.GetType().GetTypeInfo()

If you can’t find it on Type, try TypeInfo

Extension method from System.Reflection

API Portability resources

▪ Portability analyzer VS extension▪ https://github.com/Microsoft/dotnet-apiport/releases▪ http://dotnetstatus.azurewebsites.net/ ▪ https://packagesearch.azurewebsites.net/ ▪ http://forums.dotnetfoundation.org/ ▪ https://gitter.im/dotnet/corefx ▪ https://dotnet.github.io/porting *

* soon

Managing expectations

▪ This is very much a new platform with a known flavor

▪ There is a cost to migration

▪ There are things to learn

▪ Not all projects can or should migrate

Should I migrate my project?

Cannot:

▪ WPF, WinForms, unless UWP

▪ ASP.NET WebForms

Should (absolutely):

▪ General purpose libraries

Should (maybe):

▪ ASP.NET MVC

▪ Micro-services

▪ Console apps

▪ Rewrite

▪ Talent expertise on Linux

DEMOPorting FluentPath

Dependencies

▪ Most fundamental libraries first: test frameworks, tooling, data access, JSON, logging, IoC, etc.

▪ Go to the source, ask the author

▪ Offer to help, or fork

▪ Switch to another Core-compatible library

▪ DIY

Testing

▪ xUnit was first, now NUnit, MsTest

▪ Secondary test libraries (mocking, functional testing, etc.) in progress

Debugging

▪ On Windows: Visual Studio

▪ Everywhere: VS Code

Tooling

Your choice of tool, on your choice platform

▪ Visual Studio on Windows

▪ Visual Studio Code on Mac, Linux, or Windows

▪ vi or emacs with OmniSharp

▪ etc.

.NET CLI replaces DNX, DNVM, DNU

▪ dotnet new

▪ dotnet restore

▪ dotnet run

▪ dotnet build

▪ dotnet build –native

▪ dotnet dosomethingcool

Scaffolds a minimal app

Restores packages for the project

Compiles and runs the app

Compiles to IL

Compiles to a single executable

You can build your own commands

DEMOCreating a new application

Q&A