First Look At ASP.NET Core 2.1 Preview One - Convert Existing .NET Core Application To .NET Core 2.1

Below is what I do to check.

Write the dotnet -version command to check the version.

As you can see it is showing the correct version.

One quick step to check if the application is converted to .NET Core 2.1 is to check whether you can see SignalR support because SignalR is sailed with .NET Core 2.1.

Open Startup. cs class and in Configure method, write app.UseSignalR.

If .NET Core 2.1 is installed correctly, then you should see that in IntelliSense.

Let us create a .NET Core 2.1 application from scratch.

Open your Visual Studio 2017 -> Create New Project -> Select Core Web application.

Click on OK and in the next window, select Web Application (MVC).

What is changed in the default code and structure?

Once the application is created, open Program.cs class, you will some changes here.

• BuildWebHost is changed to CreateWebHostBuilder
• The return type of the method CreateWebHostBuilder is changed to IWebHostBuilder – along with other changes

The new method looks like this.

public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
    WebHost.CreateDefaultBuilder(args)
        .UseStartup<Startup>();

Now, open Startup.cs class.

In the method ConfigureServices, you will see the below code.

services.Configure<CookiePolicyOptions>(options =>
{
    // This lambda determines whether user consent for non-essential cookies is needed for a given request.
    options.CheckConsentNeeded = context => true;
    options.MinimumSameSitePolicy = SameSiteMode.None;
});

This code is for GDRP. This is a new cookie consent feature that will allow you to ask for (and track) consent from your users for storing personal information.

Apart from this, by default, HSTS is added with the .NET Core 2.1 application, I have written a post on the same which you can find here.

So below are some default codes added to the Startup.cs class.

• app.UseHsts(); is added by default for the HSTS support
• app.UseCookiePolicy(); is also added by default and it enables cookie policy capabilities
• app.UseHttpsRedirection(); is also added by default which is used to redirect HTTP to HTTPS. More details here
• services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1) is also added by default which sets the current compatibility version of MVC
• 2 new files were added which are _CookieConsentPartial.cshtml and Privacy,cshtml which are mainly used to summarize your privacy and cookie use policy

Note. Please have a look here regarding all the details for the improvements of HTTPS with .NET Core 2.1 preview 1 and to run your application for the first time securely with HTTPS.

I hope it helps.